G40/G41 higher res LCD?

[solidpro]

Hi

It seems the LCDs in the G4x thinkpads are a weakness. I've had 2/3 with faulty LCDs - although luckily replacements are plentiful.

I looked at

https://www.thinkwiki.org/wiki/TFT_display

And I noticed that several screens were native 1400x1050 (11P8312 11P8298). I bought one to try and whilst it works, it's totally wrong display (everything is zoomed into the IBM logo on boot).

So I wondered, is this something wrong in the matrix on that page or was there a specific model which supported higher resolution? Come to think of it, I think I tested it on a G40, whereas the G41 I have has an upgraded graphics card in it. I wonder if that would work, or maybe a different ribbon cable is required?

One last thing - if anyone has ever broken up a G40/41 and has a spare monitor ribbon, I'd like to buy it as one of mine is damaged.

Thanks

[ajkula66]

I wonder if that would work, or maybe a different ribbon cable is required?

You answered your own question.

On pre-*60 series ThinkPads, a proper LCD cable matching the screen resolution is a must.

Happy hunting.

[kfzhu1229]

Well I have done some cable moddings for T4x, R5x 14.1" and 15" to accept all sorts of different resolutions. It's moving a bunch of hard wired jumpers around.
Since you are unlikely to find anyone else doing such mods, maybe you should look at that thread and take some inspiration from there, and maybe ask for pictures of the wiring on a SXGA+ cable.

[wujstefan]

I need to dig a bit deeper in my memory...

G51 definitely did not need a different ribbon cable for UXGA.
G41 - AFAIR - did not need a different ribbon cable for SXGA+, but I think I couldn't make UXGA to work.
G40... can't remember at all. It's sporting XGA in my garage

[FryPpy]

HMM (on top of this web page) is your friend. For G40/G41 there are some cables for XGA and some cables for SXGA+ (91P6797, 91P6822, 91P6866).

G51 definitely did not need a different ribbon cable for UXGA.

G51 - what is this?

I have'nt modded any G40/G41. But i have made mod for G50 - transplanted cable from SXGA+ G40 but used inverter board from G50 and IPS panel from T60. And it looks great. One bad thing - G50 can't take Core2Duo (Merom) CPU, only Core Duo (Banis, T2xxx) works. The main idea was to transplant HSF from G40 with top notch P4 (3GHz) and place it on top of T7600G (with unlocked multiplier) with heatspreader from P4 and... overclock it.
But it needs BIOS mod(

[ajkula66]

G51 definitely did not need a different ribbon cable for UXGA.

But that's a newer generation board - just like T60 wouldn't need a different cable - and wasn't that a G50 ? I don't recall a G51, but I may be mistaken...

[FryPpy]

And some more info.

But that's a newer generation board - just like T60 wouldn't need a different cable - and wasn't that a G50 ?

Yes newer ThinkPads like T60 use EDID to distinguish different LCDs (and LCD resolution) and do not need different cables with jumper coded resolution (how it was on older ThinkPads like T40).

BUT G40/41/50 (and R40) use LCD cables, which consist from many individual wires. In XGA version it have no wires for second LVDS channel. On a single LVDS channel it is impossible to get UXGA (1600x1200) resolution. And all SXGA+ LCDs that i know use 2 LVDS channels.

PS (teaser)
May be in near future i'll post some photos with SXGA+ (IPS) modded oldies (and some other stuff;)

[unixed]

And all SXGA+ LCDs that i know use 2 LVDS channels.

There's this single LVDS channel SXGA+ flexview:
BOE HYDIS HV121P01-100
which is fortunate for us X61 fans. It does require a modified X61 BIOS though.

[wujstefan]

But that's a newer generation board - just like T60 wouldn't need a different cable - and wasn't that a G50 ? I don't recall a G51, but I may be mistaken...

This is correct, my typo

I have'nt modded any G40/G41. But i have made mod for G50 - transplanted cable from SXGA+ G40 but used inverter board from G50 and IPS panel from T60. And it looks great. One bad thing - G50 can't take Core2Duo (Merom) CPU, only Core Duo (Banis, T2xxx) works. The main idea was to transplant HSF from G40 with top notch P4 (3GHz) and place it on top of T7600G (with unlocked multiplier) with heatspreader from P4 and... overclock it.

Yipe, this is unfortunate, yet no more punching power is needed for this baby IMO.

[kfzhu1229]

One bad thing - G50 can't take Core2Duo (Merom) CPU, only Core Duo (Banis, T2xxx) works. The main idea was to transplant HSF from G40 with top notch P4 (3GHz) and place it on top of T7600G (with unlocked multiplier) with heatspreader from P4 and... overclock it.

I think you meant Yonah, not Banias (1st gen Pentium M)
And is it not possible to modify the BIOS to get Merom working? I thought that's all that's needed for this generation

[Saucey]

It has been awhile, but I tried to upgrade a G41 SXGA+ nvidia to a A31 SXGA+ screen (or maybe it was a T42p) and the cable did not reach far enough for the screen.

[kfzhu1229]

It has been awhile, but I tried to upgrade a G41 SXGA+ nvidia to a A31 SXGA+ screen (or maybe it was a T42p) and the cable did not reach far enough for the screen.

The A30/A31's 15" screens have their connectors further down compared to a T42p/T43p. So it's likely a G41 won't reach the screen connector for a T4x/T6x panel, but it should work fine with A3x 15" panels.
I am curious though if someone would have the capability of making an extension cable for those 30 pin CCFL LVDS connectors.

[FryPpy]

I think you meant Yonah, not Banias (1st gen Pentium M)
And is it not possible to modify the BIOS to get Merom working? I thought that's all that's needed for this generation

You right it Yonah (last from Centrino family).
The BIOS modification is the main showstopper for this project... but i have not enought skills (and courage) to do BIOS mod. I understand that i can post request on bios-mods or mdl but i even have no original BIOS. There is no G50 in "Drivers" on this forum and the only place where was found information about G50 drivers (and BIOS) is Web Archive
https://web.archive.org/web/20090401215 ... J0-006F21E
But it is not downloadable.

I can make backup of running BIOS on G50 itself (with phlash utility)... but if i understand right it will be only partial image. Of course I can do full backup with programmer.

[FryPpy]

It has been awhile, but I tried to upgrade a G41 SXGA+ nvidia to a A31 SXGA+ screen (or maybe it was a T42p) and the cable did not reach far enough for the screen.

Have checked G50 with SXGA+ cable from G40 (or maybe G41) and LP150E05A2K1 - working fine.

And one more not so successful mod. I Have A20p with non-IPS SXGA+ (ITSX93C) and wanted to make it IPS. First of all this SXGA LCD have different connector (AMP 1318341-2) and it is not compatible with JAE FI-XB30SR. Ok. I've got lcd cable from A21p (with UXGA lcd) corrected jumpers so ThinkPad thinks that it is SXGA+ cable and it is worked with LP150E05A2K1, but...
Modern LCDs (from T60 and T4x) and older (from A2x and A3x) have different connector placement. So, to make this mod done i should tear and fold LCD cable but i didn't do this ;(and this A20p still non-IPS SXGA+)

[GOLB]

I put an A31p UXGA in a G41, and it just displayed the usual SXGA+ video, repeated on the bottom. Hard to describe, see below: (warning large image)

https://ibb.co/T1nLj2f

I no longer have the machine, but I've found that various SVGA machines with XGA panels do the same thing. (I have a few 240's fitted with AFFS XGA panels, and I can't for the life of me figure out how to get the machine to display full XGA! Another example below).

https://ibb.co/hLCpnXM

I suspect it's firmware / display controller related, as a fresh install of Gentoo exhibits the same issue before and after KMS:

https://ibb.co/7GCPJzK

If I figure it out on the 240's, I'll get another G41 and try the same. Hopefully that would be helpful.

[RealBlackStuff]

In the BIOS, there is a setting under Config/Display/HV Expansion, set this to On or Off.

[FryPpy]

Interesting findings.
Yes, we know that screen resolution coded with jumpers on LCD cable. So connecting UXGA LCD to SXGA+ cable says to ThinkPad that it is SXGA+ screen.
Sometimes it is possible to move jumpers on cable. Sometimes BIOS have no information (block) corresponding to new jumpers position and this trick doesn't work.

AFFS XGA in 10" ThinkPad 240 - interesting project. And the main approach - find out how 240z with XGA screen works. I can do some tests on my 240z and 240x (screen assembly swap for example), but main thing to think about: 240z have 4Mb VRAM and 240x have only 2Mb VRAM. On 2Mb it is possible to show full XGA picture, but only in 16bit colors!

[kfzhu1229]

I put an A31p UXGA in a G41, and it just displayed the usual SXGA+ video, repeated on the bottom. Hard to describe, see below: (warning large image)

https://ibb.co/T1nLj2f

I no longer have the machine, but I've found that various SVGA machines with XGA panels do the same thing. (I have a few 240's fitted with AFFS XGA panels, and I can't for the life of me figure out how to get the machine to display full XGA! Another example below).

Again, these ThinkPad models use a few jumper wires embedded into the LCD cable to determine the resolution (Typical before the introduction of EDID).
Unfortunately, there isn't anything even close to schematics for something like the 240, so you can't determine where those traces are on the motherboard side LCD connector this way.
But, if you happen to have a working XGA 240Z, then you can dissect the cables a little bit and look for traces that don't go into the LCD or inverter (and then compare to the SVGA cable to see the differences).
This is the idea behind my spottings for the ThinkPad T4x/R5x series cable mod thread: viewtopic.php?f=2&t=126717&p=853475&hil ... od#p853475

[GOLB]

Thank you all for the info! No luck with the BIOS option FWIW. I'll keep hunting for an XGA 240Z motherboard

Good to know about the jumpers / lack of EDID; I can rule out the clock+data pairs with a scope (large image here, https://ibb.co/N7zr91B, quite handy for fitting panels with unknown pinouts), perhaps a magnifying glass and some guess-and-checking with a burner 240 could help me find the right pins.

And I'll agree, the extra 2meg VMEM for 24bpp sure is nice! Best of luck with the G41, OP.

[FryPpy]

I can rule out the clock+data pairs with a scope (large image here, https://ibb.co/N7zr91B, quite handy for fitting panels with unknown pinouts)

Nice photo, with oscilloscope, multimeter, soldering station and especially with impact socket (1-3/16) on top of LCD.

My current project is R51e.
I have restored stereo speaker system but cant do SXGA+ mod.
On schematics there are hints about possibilities of SXGA+? but PSREF show only XGA R51e units.
Have tried R52 SXGA+ LCD cable with different screens - result: black screen and no backlight.
On R51e XGA LCD cable LP150E05A2K1 shows no picture, but backlight is on.
But LP150E07TL03 show XGA on SXGA+ picture similar to images in first GOLB's post.
I have tried loading EDID from Linux kernel parameter and linux kernel think that EDID is ok, but maximum resolution reported to XServer is XGA.
Tried to make new video mode (SXGA+) with xrandr but it makes funny flash image and no video output until i restart XServer. The same dead end;(

[kfzhu1229]

My current project is R51e.
I have restored stereo speaker system but cant do SXGA+ mod.
On schematics there are hints about possibilities of SXGA+? but PSREF show only XGA R51e units.
Have tried R52 SXGA+ LCD cable with different screens - result: black screen and no backlight.
On R51e XGA LCD cable LP150E05A2K1 shows no picture, but backlight is on.
But LP150E07TL03 show XGA on SXGA+ picture similar to images in first GOLB's post.
I have tried loading EDID from Linux kernel parameter and linux kernel think that EDID is ok, but maximum resolution reported to XServer is XGA.
Tried to make new video mode (SXGA+) with xrandr but it makes funny flash image and no video output until i restart XServer. The same dead end;(

Be extremely careful about the difference between XGA and SXGA+.
If you display SVGA on a XGA screen, you get that grid pattern effect where you have 4 copies of the image. Same thing if you try to display SXGA+ on UXGA.
However, if you display XGA on SXGA+ screen or vice versa, you will just get a black screen! This, is actually because XGA is of single channel LVDS signalling, while SXGA+ required dual channel LVDS! Hence, all XGA (and WXGA, WXGAHD) screens have the 2nd channel of LVDS signals completely disconnected!
If you really want to test how SXGA+ works, do NOT use a XGA screen. Use SXGA+ screen only if preferred, and if you really don't have one, try with UXGA or QXGA screen. I learnt this the hard way when trying to mod my cables to SXGA+, and my SXGA+ screen won't do anything at all until that mod is completed

[FryPpy]

However, if you display XGA on SXGA+ screen or vice versa, you will just get a black screen! This, is actually because XGA is of single channel LVDS signalling, while SXGA+ required dual channel LVDS!

I understand this but before this post i have one successful mod with R40.

Some late R40 with Centrino CPU have 15" SXGA+ screen. The mod was to get last ThinkPad with UltraBay (UltraBay plus more precise) and IPS screen and late R40 was be good starting point.
Bad news that it can't use Dothan CPU (only Banias) while T40 can use Dothan. To overcome this BIOS needs to be modded.
Other story - not every R40 can be modded to SXGA+. I've got R40 SXGA+ LCD cable connected to one of my R40 and connected it to my lovely LP150E05A2 (from my first T60 with swapped CCFL;). And it is worked but very strange. Image was not so sharp and dark.... and i make some tests before i've seen screen with high magnification.... Only even vertical stripes have shined and odd was black. After that i have checked all R40 motherboard that i have and found:
Motherboard with 16Mb Radeon 7000 have only single LVDS channel connected to display socket, while motherboard with 32Mb Radeon 7500 have both channels connected to display socket.
Yes - it can be fixed. Some 0Ohm resistors (resistor blocks) should be soldered on Radeon 7000 motherboard to get second channel connected.
But i have swapped motherboards, packed IPS screen, placed 1.7GHz CPU and 2Gb ram and got lovely ThinkPad. Last mod that was made on last weekends - i've packed UJ220 BD-RE in ultrabay plastics and it is working in this R40. Also it can use 1.44 Floppy, ZIP, LS-120/240 or second HDD in SATA caddy and numeric keypad - amazing.
BTW - UJ220 was last BD-RE with IDE interface that can be shipped with with R61 but not T61!!!

Conclusion. If ThinkPad understand that it is SXGA+ LCD even in case that cable have no second LVDS channel it can show picture. But if Thinkpad think that this is XGA LCD even SXGA+ LCD connected on dual channel cable can show blank screen (LG IPS) or distorted image (LG TN).

My question - how to override in OS this LCD selection, made by BIOS based on cable jumpers?

[kfzhu1229]

Conclusion. If ThinkPad understand that it is SXGA+ LCD even in case that cable have no second LVDS channel it can show picture. But if Thinkpad think that this is XGA LCD even SXGA+ LCD connected on dual channel cable can show blank screen (LG IPS) or distorted image (LG TN).

My question - how to override in OS this LCD selection, made by BIOS based on cable jumpers?

I guess if you have a SXGA+ cable and XGA screen then you might be able to get a picture, depending on the screen. But I have personally tried a XGA cable with SXGA+ panel on both ATI and Intel T43 models, all you get is just a black screen, and then the black screen might eventually fade to a white one, indicating the SXGA+ screen is not understanding anything at all with the 2nd channel connected but not having any data due to XGA resolution.
T30 is a different story, that thing uses a propietrary connector and might not follow any of the typical LVDS behaviours.
On the other hand, you will get a black screen too if you use a cable without the 2nd LVDS channel on things like WXGA+, SXGA+, and so on. This is a well known annoyance with the Dell Latitude D620/D630 when upgrading the LCD (same 30 pin LVDS connector).
Well I have previously tried overriding such things in the OS with no luck. I had a Compaq CQ56 with a 15.6" CCFL screen that would output XGA resolution on WXGAHD screen no matter what, no luck changing any of that in the OS with integrated graphics (Turns out it was LCD cable fault causing EDID data to not get through).
If you have a modern graphics with recent drivers like from the NVS 140M, then there is a chance you will get a picture once you boot into Windows and GPU drivers are loaded.
That's totally not gonna happen with the old Neomagic chips whose drivers don't have control over this. But again if you need help figuring it out yourself with a comparison between the SVGA and XGA cables, then my guide for that might be helpful.
For one time testing of jumper configurations without causing irreversible damage to the cable, you can try things like using kapton tape to insulate certain pins, and to use conductive ink pen to connect a few traces (easily reversible with alcohol wipe). Of course you can still cause damage to the screen and motherboard, but you won't be out with the precious LCD cables.

[FryPpy]

And the main approach - find out how 240z with XGA screen works. I can do some tests on my 240z and 240x (screen assembly swap for example)

SORRY FOR SOME OFFTOPIC:(

Results from testing (display swap) between 240z and 240x.
240x with XGA display from 240z show only white flash in lower 1/3 of screen. Even when windows started up nothing changed:( black screen with distorted white on lower 1/3 of screen)
But 240z with SVGA display from 240x works fine. Windows detects that it is SVGA screen... So 240z can distinguish different screens (jumpers on cable?), but 240x can't... Dead end.

Some more thoughts. 240z mother board have internal LAN and LAN socket, but 240x case have no hole for LAN socket.
There are rumors, that some iSeries 1124 had XGA screens... but i have no info about such ThinkPads. My 1124 have 450MHz celeron, 2Mb LynxEM+ and SVGA screen with vinegar syndrome;(

[kfzhu1229]

Results from testing (display swap) between 240z and 240x.
240x with XGA display from 240z show only white flash in lower 1/3 of screen. Even when windows started up nothing changed:( black screen with distorted white on lower 1/3 of screen)
But 240z with SVGA display from 240x works fine. Windows detects that it is SVGA screen... So 240z can distinguish different screens (jumpers on cable?), but 240x can't... Dead end.

Some more thoughts. 240z mother board have internal LAN and LAN socket, but 240x case have no hole for LAN socket.
There are rumors, that some iSeries 1124 had XGA screens... but i have no info about such ThinkPads. My 1124 have 450MHz celeron, 2Mb LynxEM+ and SVGA screen with vinegar syndrome;(

If you indeed used the tested good XGA cable with 240X in addition to the XGA screen and still it isn't working, then unfortunately it's game over. At that point it's basically a combination of the BIOS not knowing what XGA looks like and also the motherboard might be missing the signals from the jumpers on the LCD cable entirely, in which case a XGA screen would still be treated as a SVGA, like on a big barrel charger plug if the centre pin is missing.
If you know how to mod BIOS, maybe copy some codes off a 240Z BIOS image and see if there is anything there.