I added more 128 MiB of RAM into my computer. I've tried adding 256 MiB, but my mother board didn't recognized it :-(
Now, I have 256 MiB of RAM. The machine is a lot faster and the disk is almost never accessed --- before it swapped a lot.
If anyone knows of any trick to make an ASUS P2B 99 to recognize a chip of 256 MiB of RAM (1 chip of 256 + 1 chip of 128 = 384 MiB total), I'd be interested --- even though I don't have the 256 MiB chip anymore.