Disk read error after setting CPU clock

[GeeWhat]

Okay, so I tried fixing up this (really) old PC while I wait to get my new PC within the next 1 or 2 months. I've built PCs often, I've fixed PCs often, but I'm stuck on this one. Before I continue, here are the specs:AMD Athlon XP 1900+ CPUAMP(D) N1996 Mobo1 x 1Gb DDR 400 RAM1 x 512Mb DDR 400 RAMForsa Nvidia GeForce 6600 256Mb Graphics cardLAN card, USB hub, a DVD RW, 160Gb HDD and a 80Gb HDDSo, I took it apart, used my static band, breadboarded, replaced the 512Mb DDR 400 with another 1Gb DDR 400, and started up. Then the problems started.After struggling for a week, receiving a different set of errors every time, I decided to replace the HDD. It worked well. Albeit not worth saving, I could still play a mean SCII skirmish.This morning, after getting utterly frustrated with the lag when my unit cap got to 100, I sat down and considered the consequences of changing the CPU clock. Apparently, for the CPU, 133 is a safe clock, and I checked the CPU temp, which was within operating temperatures. Once in the BIOS, I noticed the clock has the option of an integer between 100 and 132 (yeh, 132), which confused me. I then realised it uses a 12.5 multiplier. I moved the clock up, saved, then sat back and waited for the boot.It ran, I got into a skirmish, but then everything froze up, got all weird, and I hate to reset.I was rudely greeted by a "Disk read error, press ctrl + alt + delete to restart" once it was ready to boot Windows. I received this once or twice during my initial build.I tried setting the clock to 100, and many others, with the same result.A few notes:HDD is newRAM is in properly, and workingCPU is functioningNo power-supply problemsDVD RW and HDD run at startupEverything else I checked out. The PC is fine.Any help? I need to fix this up. No skirmish for more than a month? That's sick. lol