About the ThinkPad A21 A22 etc Series

[BillG]

I have a 700MHz 15" ThinkPad A21e laptop, 2628-JCU. The LCD screen is bright and brilliant to see!

It would make me happy to do a cheap upgrade of the CPU to the fastest speed possible, whicn I think (I'm not sure) is a 1GHz microPGA2?

What is strange is I also have another 700MHz 14.1" A21e, a 2655-41U, which has a smaller case but identical internal specs.

I see curious similarities between the A21e, A21m, A21p, A22m, and A22p models.

I think that the differences are:
- The A21e has Celeron 700MHz with 1024x768 screen
- The A21m has P3 800MHz with 1024 x 768 screen
- The A21p has P3 850MHz & 1600x1200 screen
- The A22m has P3 1GHz & 1400x1050 screen
- The A22p has P3 1GHz & 1600x1200 screen

Can anyone tell me if there a compatibility guide between these models? ARE MOTHERBOARDS COMPATIBLE for the same screen size?

[sjthinkpader]

A21e/A22e
Type 2628 are in the three spindle case and CPUs are socketed. Type 2655 are in a two spindle, T2x like case and CPUs are soldered. They have 13.3 or 14.1 LCD. Unlike T2x, they only accept 9.7mm HDD.

A22m
Only 2628-Sxx have SXGA+ LCD. This is only common to A20p.

Some people had reported 850Mhz CPU MBs can run 900/1Ghz CPU. My experience is that only 900Mhz/1Ghz MBs are CPU interchangeable. But most of my machines are now gone and I can't verify that anymore.

The 2628 series MB are LCD resolution specific. You have to change MB to change resolution.

There are many different fan/heatsinks.

[ajkula66]

A22e also came with a 850Mhz Pentium 3 CPU, but these are fairly rare.

A21p and A22p have appeared in various guises when it comes to CPUs, anywhere from 800 Mhz to 1Gb. The same goes for A22m.

[schen]

I've also come across an A22m that had a soldered CPU.

[agarza]

I still have one A22e with Celeron 800MHz, I had a choice at the time of buying the laptop to get the PIII 800MHz, but went with the celeron, I saved about 300USD, after all it was intended to use as a college laptop.