I have an Inspiron 1100 with 512k (2 chips). A couple of months ago, it started displaying a “Memory configuration has changed” message when it booted. Sometimes it found 512k, but mostly 256. I swapped the chips, eraser’d them both, tried one chip in Dimm A, then B, swapped the other chip into A & B with no change. With both chips installed, it only sees 256k. The chips are original from Dell. It will only see 256k no matter what. I have not changed any hardware or software, although I refreshed XP (SP2) just to be sure. If I just need a new MB, so be it! Any ideas?

run memtest 86+ for at least 7 passes. boot from a floppy or cd rom