IBM ThinkPad T22 Series (Type 2647)

As a note, as long as both RAM modules are PC133, you can use that, too, but you're still limited to 2x256MB. PC133 seems to be more readily available for purchase and a good deal cheaper than PC100, so it's good to know.

Since this is an older machine, the performance can't be boosted very much. The maximum performance you can get from this machine is 1ghz processor, with 512mb RAM. The 1ghz processor is the biggest processor that is compatible, and unfortunately, the system is base on a 100mhz frequency rating, so PC100 memory is the only compatible memory available. The maximum chip size in PC100 is 256mb, they just don't make them any bigger, so 2x256mb=512mb RAM. As far as the hard drive, it is an IDE drive, and you can get an IDE drive up to 120gb. These are very good and durable machines, just slow, so if you can deal with the lower level of performance, this machine will last years. Also, these are upgradeable to XP pro, but not Vista.