My performance problem and how I solved it

I finally put another 512MB of RAM in my office Linux box today. It has had "just" 512MB forever, while I waited for the price to come down. I had all kinds of data that suggested the machine was short on RAM, and that adding more would dramatically improve its performance…

The scary part is that it worked. After I closed up the box, opened it up again and seated the memory module properly, undid some BIOS tweaks that were keeping the BIOS from seeing the new memory, closed up the box again and booted Linux, things that had been disk-bound and taken maybe ten or fifteen seconds suddenly began to take just one or two.

I'm not sure I'm happy about this. What on earth would my little desktop Linux box want more than 513MB of RAM for?

I'll try to gather some more information. Advice on the best way to do this is appreciated. Perhaps sometime soon, my box will use less than 512MB. In the meantime, for $50 and an hour of my time, I've solved my performance problem. Who knew? (B)