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PostPosted: Wed May 16, 2012 4:38 pm 
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Hi All,

I was reluctant to post this topic because it sounds so bizarre. But I figured I would share my experience, for whatever it's worth.

I recently purchased an X220 and was quite happy with it. But in the first couple of weeks, I only worked on it off the battery. When I had occasion to plug it in and work on it, things changed. Within 10 or 20 minutes, I had headaches, felt slightly nauseous and developed a condition I can only describe as "brain fog".

I turned off the machine and got away from it for a while. It took me about a whole day to feel normal again. I tried to figure out why this had happened. Maybe it was some psychosomatic condition brought about by dealing with a smaller screen than I was used to. Maybe it was eyestrain in some way because I do have the aging eyes of a middle aged guy and I am used to a different screen resolution.

But then a couple of days later, I gave it another shot but this time plugged in an external monitor that I normally use. I got the same result -- brain fog and nausea with 10 minutes. That effectively ruled out the eyestrain explanation.

Since I didn't want to only use the laptop off the battery, I returned the machine to Lenovo. The customer service person I spoke to had never heard of this problem. He may well have thought I was some kind of nut and I guess I couldn't blame him. It sounds crazy. But he accepted my return, although I did lose the 15% restocking fee as per the return policy.

So now I'm still in search of a new computer to replace (or supplement) my T60. Today, I checked out a Thinkpad E430 at a local shop just to see if this was a possible candidate. Lo and behold, I got sick after using it for 10 minutes in the shop.

If anyone else had this experience, I would like to hear about it. I recognize this is pretty rare since I googled it and didn't find anything that stood out. And yet, I can't believe I'm the only person that has had this reaction to this generation of computers. So what is causing it? The Sandy Bridge chipset and its higher speeds? This is possible since I felt fine when it was on battery power when it could reduce performance and speed in order to conserve power.

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PostPosted: Wed May 16, 2012 4:54 pm 
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You display refresh rate may have been wonky. Display refresh rate issues can cause the kind of severe nausea and the kind of sickness you are describing.

See this. Lots of other comments on Google as well.

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PostPosted: Wed May 16, 2012 5:43 pm 
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Possibly an auditory thing?

http://communities.intel.com/thread/25158
http://en.wikipedia.org/wiki/Sonic_weapon

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PostPosted: Wed May 16, 2012 10:02 pm 
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Thanks for your sincere replies.

I don't think it's a sound issue, since I didn't hear anything.

The monitor and refresh rate issue sounds more plausible, although I would note that I felt also sick when I was using my external monitor. This was the same monitor I always use. AFAIK, I don't think Windows 7 can alter the refresh rate of a monitor.

So I'm less inclined to think that it is visually related.

So the mystery continues. I'm still leaning towards a processor/EMF type explanation, although I have idea why this would be the case. I will try to use some other laptops to see what reaction I have.

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PostPosted: Wed May 16, 2012 11:01 pm 
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Maybe you should try to sit next to it but with screen off or behind your back, to rule out the refresh rate issue.

Then you could try some ear plugs or headphones to rule out sound. The fact that you didn't hear anything doesn't rule that out.

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PostPosted: Wed May 16, 2012 11:20 pm 
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Do old fluorescent lights also make you sick?

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PostPosted: Thu May 17, 2012 9:56 am 
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ctoph0 wrote:
Do old fluorescent lights also make you sick?


Not that I know of.

I am likely more sensitive than most people. I tend to avoid big screen action films because I am prone to motion sickness. I don't read in the car or the bus for the same reason. So there is a sensitivity there with vision and motion. But that's different from a laptop that isn't moving at home or work, especially one that is plugged into an external monitor. Also, remember that I was fine when the laptop was running off the battery. Would different power management schemes change screen refresh rates? I don't think so. Only screen brightness and I would often crank up the brightness to full while on battery with no ill effects.

I know that there are some people who like to blame EMF emissions for all sorts of mysterious illnesses. But there is no conclusive evidence in that area, although there may be people who are more sensitive to it than others and this may not show up clearly in large scale studies. I actually went out a bought an EMF gauss meter to satisfy my curiosity. No surprise -- the EMF coming off the X220 was completely normal. Just around 1 milligauss at a distance of 1-2 feet. This is the same measurement that my T60 produced. But then again it may be possible that the simple amplitude of the field is not a key factor.

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PostPosted: Thu May 17, 2012 12:37 pm 
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Only problem I can think of is flashing backlight. Even LCDs don't blink like CRTs, backlight on LCD panels on lower brightness does! When you set backlight to another value but 100% it won't simply dim - it rapidly turns off on, off, on to fool your eyes that it is dimmer. When you have 100% brightness it is constantly on and there is no problem. Search PWM on wikipedia.

Another thing is even you have set 100% backlight in lenovo powermanager, when you run on battery the screen will be little dimmer and again the screen is flashing. It is because "dynamic brightness" and another setting in Intel graphic adapter which regulates brightness when on battery even you have full brightness in lenovo power manager!
It is somehow automatically regulating brightness according displayed picture - when you have dark scene it dimms or something like this..

Here I made screenshoot - uncheck these 2 checkboxes at the bottom

Image

I hope it will help.

EDIT: I made a video how to know the backlight is not linear and flashes - you only need some pen and fast fingers. It is actually much better visible with naked eye but for demonstration it is enough. Watch in HD

http://www.youtube.com/watch?v=KN16EWIRwxg

First I use it at brightness level:15 and AC connected - you see just normally blurred pen
Then I disconnect AC and brightness setting is still 15 but "dynamic brightness" is enabled - you can see the pen is blurred differently- there are visible darker and brighter spots.
To make it more visible on video I connected AC again and set brightness to level 3 - you can clearly see that something is really not OK and it is not just "simply dimmer"


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PostPosted: Fri May 18, 2012 4:01 pm 
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Wow, thanks for sharing your ideas. Much appreciated! I don't quite know what I'm looking at in the video however although I accept your basic point: the screen is not exactly the same when it is set at 15 on battery and on AC.

I'm open minded about this whole thing. And yet, the fact that the symptoms returned while watching on my regular external monitor makes me think that the the screen is not the problem.

I'm quite busy today so I will have to look into this again in more detail over the weekend.

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PostPosted: Fri May 18, 2012 4:14 pm 
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It's been mentioned before in this thread, but you sort of blew it off as impossible, but... the more I read about what you have already tried, I suspect it is auditory. I imagine your AC adapter is creating an ultrasonic, high pressure sound wave that is causing your symptoms. You likely will not "hear" anything unusual, but it certainly can have a negative effect on your system.

If you can borrow another AC adapter, switch them out and see if it makes any difference. Or, maybe just isolating the adapter in a desk drawer, or another room or something to protect your ears. Just experiment with it. It could be the cause.

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PostPosted: Fri May 18, 2012 6:33 pm 
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Thanks for weighing in, Neil. I appreciate all suggestions.

That's an interesting idea.

The thing is I have an apparently identical AC adapter for my T60 that causes me no problems. It's possible there are somehow different inside, but I kind of doubt it.

It is possible that there are high pitched sound waves emanating from the processor or motherboard that can't be heard but still felt by the brain. Nonetheless, I will look into the whole auditory dimension more.

I hope to do some testing with other laptop computers over the weekend just to see what happens. The trouble is if I do get sick it only takes about 10 minutes, but then it takes the next few hours to recover. Very time consuming and not much fun. :(

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PostPosted: Fri May 18, 2012 6:57 pm 
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If you ruled out display I really don't know. btw I had problems with my desktop monitor which uses also PWM to controll brightness - but it won't matter if AC is connected or not. Maybe the power adapter is faluty and making some high frequency noise? I run a test - I have sound spectral analyzer istalled on my cell phone (android). I placed it on my power adapter (65W) and i found it creates high frequency noise when the laptop is connected but off (it has only little drain which those switching power supplies don't like)
Here are the results - when the laptop is switched off there is some nosie at 15 and 6 kHz (first pic) there is also some noise when te laptop is disconnected (second pic) and when the laptop is powered on and connected there is almost nothing (third pic). However intensity is very low and you won't hear it unless you have ear on the adapter

http://img221.imageshack.us/img221/2313 ... hot1sq.jpg
http://img138.imageshack.us/img138/3928 ... hot2qw.jpg
http://img31.imageshack.us/img31/8532/screenshot3zj.jpg

I also checked noise directly from laptop - there is also some noise but it won't change when running n AC or battery. Please note I have x220i Tablet so it could be little different
Image

(ignore vertical lines - it is scanning from left to right and it is not easy to be 100% quiet during all scan :-) )


Last edited by JaneL on Fri May 18, 2012 8:11 pm, edited 1 time in total.
No pic warning and no pics >50k.


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PostPosted: Sat May 19, 2012 2:57 pm 
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I would say that the AC adaptor theory sounds very much like it could be the issue. When I got my first ThinkPad back in 2009, an R500- the PSU made a noticeable electrical whine, which used to give me a headache within 30 minutes of using the laptop with the AC adaptor. I decided to buy another AC adaptor, as I was going to need a second anyway, and the AC adaptor I bought didn't make the same whining sound, and as such, I didn't get any headaches when using this AC adaptor.

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PostPosted: Sun May 20, 2012 4:08 pm 
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OK, a breakthrough of sorts.

To yak, Easymac308, Neil and Matt, you're all probably right. I now do think it is auditory.

Here's what I've found out. I had forgotten that soon after I got my trusty old T60 back in 2007 I had turned down the speed of the processor on AC power in order to keep the fan from coming on. I got one of the noisy T60s (BIOS 2.xx), and the fan noise was driving me nuts. So in addition to installing TP fan control, I decided to reduce the power going through the CPU. As a result, my processor on AC ran at the same speed it ran on while on battery -- just 980 Mhz instead of its maximum 1.6 Ghz for the Core Duo T2300.

So when I changed the power management settings and set it to maximum performance, presto -- I got the familiar symptoms of nausea and brain fog within just 30 seconds!

Moreover, when I wore some decent earplugs (33db), I didn't get sick. So that's really useful information for the future.

Now I'm not sure exactly where the auditory disturbance is originating. Remember that I don't hear anything abnormal coming from the computer or the adapter for that matter. It could be the processor, the adapter, or the motherboard. Who knows?

My next step will be to try to physically isolate some of these things to see how it affects the overall picture. If I can get far enough away from the computer, then that could reduce my symptoms.

It's tempting to think I could stash the laptop in a solid box or something, but then the absence of ventilation would create heating issues.

Still, this is a big step forward in this mystery. And I owe a big thank you to everybody who made constructive suggestions. I'm really grateful to everybody who posted. :thumbs-UP:

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PostPosted: Sun May 20, 2012 4:14 pm 
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matt340 wrote:
I would say that the AC adaptor theory sounds very much like it could be the issue. When I got my first ThinkPad back in 2009, an R500- the PSU made a noticeable electrical whine, which used to give me a headache within 30 minutes of using the laptop with the AC adaptor. I decided to buy another AC adaptor, as I was going to need a second anyway, and the AC adaptor I bought didn't make the same whining sound, and as such, I didn't get any headaches when using this AC adaptor.


That's very interesting.

Was the second adapter the same wattage etc and was it also made by Lenovo? I'd like to know more of the specifics here.

I will examine this possibility in greater detail.

Thanks for posting!

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PostPosted: Fri May 25, 2012 1:32 pm 
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Just in case, it'd be worth looking at EHS: http://en.wikipedia.org/wiki/Electromag ... ensitivity

A possible scenario would be that plugging the X220 on AC would provoke some electromagnetic changes, somewhere and somehow (screen, chipset, you name it) to which your brain/body would negatively react.
And you wouldn't have felt that way with your T60 because this previous generation may be better shielded and/or its different components do not emit the same waves.

In any case, you're not crazy. Such phenomenons are real, yet totally unsufficiently documented.

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PostPosted: Fri May 25, 2012 3:37 pm 
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hirst60 wrote:
That's very interesting.

Was the second adapter the same wattage etc and was it also made by Lenovo? I'd like to know more of the specifics here.

I will examine this possibility in greater detail.

Thanks for posting!


The second adaptor was exactly the same as the first (exactly the same FRU I remember, though I don't recall the FRU), so the same wattage.

On a side note, I purchased the Lenovo Slim 90W adaptor a while ago, when I was still had my X301, and when connected this had a similar noise, though on a lower scale, that didn't seem to cause me headaches. The factory power supply for the X301 is 65W, which I have had (and still have, for my X220) about 4 or 5 over the last 2 years- none of which have caused any noise. I have since got rid of the 90W adaptor (due to the noise increasing when I took it on a trip to China, using it with a UK to China plug adaptor- though I think the increase in noise may have just been coincidence, or possibly just because the location I used the PSU in was more audible). I don't know if this information really helps you though.

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PostPosted: Sun May 27, 2012 5:38 pm 
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One thing that I don't think was mentioned here was off-gassing. Certain new products such as electronics, can actually release some gasses as they heat up. The gasses are usually emitted from the paints and epoxies as they “burn-in”. Some people are more sensitive to these gasses and exhibit the symptoms that you described. Just something to consider…


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PostPosted: Mon May 28, 2012 11:37 am 
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Summilux wrote:
Just in case, it'd be worth looking at EHS: http://en.wikipedia.org/wiki/Electromag ... ensitivity

A possible scenario would be that plugging the X220 on AC would provoke some electromagnetic changes, somewhere and somehow (screen, chipset, you name it) to which your brain/body would negatively react.
And you wouldn't have felt that way with your T60 because this previous generation may be better shielded and/or its different components do not emit the same waves.

In any case, you're not crazy. Such phenomenons are real, yet totally unsufficiently documented.



Thanks for suggesting EMFs. I agree it is something that is undocumented and unfortunately largely ignored. I suspected this might be involved in my symptoms and even went so far as to purchase a gauss meter that measured AC electromagnetic fields. But I found that the readings were roughly similar between the X220 and the T60 (around 1 mG at a distance of 2 feet) and generally within acceptable limits. But I did note that the needle went off the charts (>10) on the underside of the machine when it was plugged in. This was a reminder that working with laptops on one's lap may not be a good idea, especially when on AC power. Readings under 2 or 3 are considered generally safe, whereas readings over 10 are not. It is not known how dangerous those levels are, but one should practice some caution when in close proximity.

It is conceivable that total magnitude of EMFs may not be the only problem but rather one has to look at the wave shape or orientation. But given the fact that my symptoms largely subsided when wearing ear protection, I think I can rule out the EMF hypothesis in my case.

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PostPosted: Mon May 28, 2012 11:40 am 
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jts_01 wrote:
One thing that I don't think was mentioned here was off-gassing. Certain new products such as electronics, can actually release some gasses as they heat up. The gasses are usually emitted from the paints and epoxies as they “burn-in”. Some people are more sensitive to these gasses and exhibit the symptoms that you described. Just something to consider…


Very true, and I did notice the plasticky new computer smell at the beginning. Not pleasant, but it was not harmful in my case since my original T60 also made me sick when I cranked up the processor speed to maximum performance at 1.6 Ghz.

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PostPosted: Tue May 29, 2012 7:06 pm 
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jts_01 wrote:
One thing that I don't think was mentioned here was off-gassing. Certain new products such as electronics, can actually release some gasses as they heat up. The gasses are usually emitted from the paints and epoxies as they “burn-in”. Some people are more sensitive to these gasses and exhibit the symptoms that you described. Just something to consider…

^this can be a possibility. I'm one of those people sensitive to off-gassing. I remember getting my brand new T43 for the first time and it was the new smell that actually made me vomit a few times. When I think back I lol :lol: But I learned from that experience and with my X201s I let it air out (left the window open) for a few days before really using it.

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PostPosted: Wed May 30, 2012 2:32 am 
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Here's one confirmation that it's auditory... My 20 year old daughter just called me out to the kitchen where she said that there was a "squeaking" noise coming from the X60 that I leave on the table. Sure enough, the 90W Lenovo adapter sitting on the hardwood floor was making a high-pitched scratching sound. I had to put it up to my ear in order to clearly hear it but she said that for the last few days, every now and then she could distinctly hear it over 15 feet away. It was annoying for her but not enough to physically make her sick. Replaced it with another 90W unit and all is quiet (for now).

edit: Sorry, the "noisy" unit is FRU P/N 92P1106, marked with a Thinkpad label on the front and an IBM logo on the back with the words "Manufactured for Lenovo". When left plugged in the wall socket but not connected to the X60, the high-frequency scratching sound changes to a lower frequency "buzz". This adapter was connected to the X60 24/7 but the laptop is normally off. The silent unit is FRU P/N 42T5277, engraved with Lenovo on the front and Lenovo (not IBM) on the back.

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PostPosted: Wed May 30, 2012 4:13 am 
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would also like to add my opinion FWIW. Didn't see it written in this thread, but just because a power supply is new, or the same as the one you already have, ie model voltage etc, doesn't mean it isn't faulty in some way. I would hate to think that the 'faulty' power supply is still being used and causing an unnecessary health risk.

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PostPosted: Sun Jun 24, 2012 1:54 pm 
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Oh yeah, I've had plenty of laptop adapters squeal. Actually, not just adapters -- I've had lots of other devices with squealing components. IIRC it's caps and inductors that are usually to blame.

And no, squealing isn't necessarily a sign of impending failure. (Buzzing from arcing, however, definitely is. But that tends to be accompanied by other symptoms...)

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PostPosted: Sun Jun 24, 2012 1:57 pm 
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hirst60 wrote:
It is conceivable that total magnitude of EMFs may not be the only problem but rather one has to look at the wave shape or orientation. But given the fact that my symptoms largely subsided when wearing ear protection, I think I can rule out the EMF hypothesis in my case.


Well... we can rule out EMF sensitivity since -- well how do I put this? -- it's not a real thing.

From the linked Wikipedia article:

"The symptoms described by 'electromagnetic hypersensitivity' sufferers can be severe and are sometimes disabling. However, it has proved difficult to show under blind conditions that exposure to electromagnetic fields can trigger these symptoms. This suggests that 'electromagnetic hypersensitivity' is unrelated to the presence of electromagnetic fields, although more research into this phenomenon is required."

Sensitivity to high pitched noises, or a reaction to some of the materials used in manufacture seem to be much, more likely explanations.

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PostPosted: Sun Jun 24, 2012 2:09 pm 
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I am not sure what causes the OP's problem. So many possible causes have been suggested! :wink:

However, I can share a small personal experience. A few days ago I got to briefly use a friend's X220 with an IPS panel. He has WinXP installed with the standard blue background (no wallpaper image). A few times during use I could clearly notice flickering of the screen. It wasn't always there, or maybe just wasn't always visible. Said friend mentioned he has observed it at times.

One thing I thought is that it's the automatic refresh rate reduction to 50Hz, but it seemed as if it was on 60Hz in the display properties. Maybe we haven't looked in the correct place, though?

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Past: Z61t 9440-A23, T60 2623-D3U, X32 2884-M5U


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PostPosted: Mon Jun 25, 2012 3:15 pm 
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Joined: Fri Dec 24, 2010 8:02 am
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Location: Paris (Latin Europe)
ThinkRob wrote:
Well... we can rule out EMF sensitivity since -- well how do I put this? -- it's not a real thing.

Ok. Don't take it personally Rob, but what you wrote is criminal.
Science doesn't know much about the brain yet, so you cannot simply assert that "it's not a real thing".

I'm a tinnitus sufferer and for 40 years "experts" have claimed that this condition was a "psychological" trouble. But only recently has the scientific community discovered that there are indeed abnormal neuronal activity and other physiological changes in patients' brains.

People have been taken to mental hospitals because they were deemed "crazy", you know. Just because medicine was too backwards to understand how the brain works and how it can be affected.

Now, here is a link to a scholar article, Electromagnetic hypersensitivity: Fact or fiction?, stating that:
Quote:
Recent evidence suggests pathophysiological change in some individuals with EHS.

http://www.sciencedirect.com/science/ar ... 9711012733

Sorry if that was a bit off-topic (well, it's still related somehow), and again, nothing personal here.
Reading such assertions just make me cringe because they have grave consequences, and are frequently uttered by irresponsible doctors.

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PostPosted: Mon Jun 25, 2012 5:02 pm 
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ThinkPadder
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Joined: Tue Aug 08, 2006 2:08 pm
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Location: Hong Kong
Could it be a 6/8-bit dithering issue if the screen is related.

Cheers.


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PostPosted: Wed Jun 27, 2012 11:38 pm 
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Senior ThinkPadder
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Joined: Wed May 20, 2009 9:54 am
Posts: 2342
Location: near RTP, NC
Summilux wrote:
Science doesn't know much about the brain yet, so you cannot simply assert that "it's not a real thing".


Ok, so you're right -- that was a little harsh. And yeah, *some* types of EMR are bad news (example: standing in front of a high-power microwave data link... you'll definitely feel that.) But there's pretty good reason to remain skeptical of sensitivity to the sorts of EMR that are generally recognized as safe (802.11b/g/n, for example.)

Then again, even if it is somatoform, isolation from EMR would be an effective treatment... :D

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PostPosted: Sat Aug 11, 2012 2:15 am 
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Joined: Sun May 03, 2009 2:16 am
Posts: 13
Location: Berkeley, California
The organizations that review laptops, computers and monitors definitely need to look at health factors, not just performance issues. I've just been reading--again--what little I can find on how low PWM (pulse width modulation) frequencies in the LED backlight circuitry used to "dim" most screens in laptops today cause headaches and eyestrain. Clearly, it's a serious but largely unrecognized problem for a large minority of users. I suspect Lenovo, Apple and the other main offenders know all about the problem but choose to ignore it in their efforts to squeeze every minute of battery life out of their laptops at the lowest possible cost. Toshiba and a few others have long used more sophisticated (but evidently more expensive) schemes to dim LED backlighting in at least some models, such as higher PWM frequencies and progressive switching off of LED banks.

I'm sure once the public becomes aware of the problem, laptop makers will spend the extra $0.10 needed for sane backlighting. Meanwhile, I would not buy a laptop with LED backlighting without first using a photocell and scope or frequency counter to make sure its PWM frequency was >200hz. In fact, at present CCFL backlighting is a much better bet. While CCFL also involves PWM to adjust brightness, the frequencies are much higher, well into the khz range, where the eye muscles can't react; and, as an added bonus, the florescent techology involves some persistence of light output, unlike the instant on/off of LED. My latest laptop is a used Thinkpad X200 with CCFL backlighting--the last X model to use CCFL, I believe; but be careful, as some X200 variants did use LED backlighting...


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