If you are like me and want an SSD inside your laptop, but don't want to spend the extra (insert appropriate amount and currency), then you probably have thought of buying the HDD version and replacing it yourself. Doing this is cheaper AND gives you an additional 2.5" HDD, which you can use however you like. But there is a problem, which you might have already encountered or will encounter: The ThinkPad X220 only supports hard drives with 7mm thickness. You could go ahead and get an expensive Intel 7mm (I think they are the only ones to build 7mm SSDs), but here is my (cheaper) approach:
I bought the crucial M4 with 128 GB capacity (CT128M4SSD2), which is a standard 9.5mm 2.5" SSD:

Upon trying to fit it into my laptop as a 9.5mm version (see: German thinkpad forums) I noticed that you could disassemble the SSD without voiding the warranty. The M4 is comprised of two metal sheets covering top and bottom, the circuit board and a plastic spacer between circuit board and top sheet. The spacer measures about 3mm in thickness, so the SSD was < 7mm thick after removing it. The original screws (black) were way too long at this point, so I got other M2-screws (brass in my case) from a hardware store and cut them off at the appropriate length.

One more issue to address here: Some of the SMDs were sticking out higher than the memory chips on the circuit board so they would touch the metal cover. As everyone knows, touching electronics with metal usually causes unwanted results, thus I had to prevent them from touching. As you can see in the picture, I stuck some tape to the cover at the appropriate locations.
After putting everything together, I had a perfectly functioning 7mm SSD, which I could then build into my ThinkPad.

I don't know whether this works with other models made by Crucial, let alone other manufacturers. If you happen to come across another SSD, which allows this hack, please tell me and I will edit this post.
Greetings,
Slevin Kelevra
mod edit: converted large photos to thumbnails per forum rules and fixed broken URL.




