Memory Issues

[c1eddy]

Hi. I'm new here. Glad I found ya!
Picked up an A21e (Celeron model) off of eBay for a wunerful price. It had only 128mb of memory. Added 128mb more. Now...it will detect 256mb for anywhere from 1 to 4 startups. Eventually it begins running slowly...and I routinely find that it is only detecting 128mb. Once I re-seat the sticks it begins detecting 256mb again, though this sometimes takes a couple tries. What may be goin' on here? I've tested the sticks in another Thinkpad and had no issues. The clips seem to be in good shape...and the memory never appears to have worked loose in any way. They are the IBM recommended 128mb pc100 (16M X 64), FRU 20L0265 sticks.
Is there a particular sequence I need to follow to make the upgrade "stick"? Any help is greatly appreciated.

[sjthinkpader]

Welcome to the forum.

Use a drafting rubber eraser, the white kind, and rub it across the gold colored contacts of your SODIMM, both sides. Put it back and see if it is better.