I gave my old Athlon XP 2800 to my mom. I built it myself and it has an Epox 8RDA+ motherboard. A week ago she said when she turned it on it beeped and nothing came on the screen. I had my dad look at it and he said the CPU fan wasn't running. This was the fourth or fifth time we had turned it on to troubleshoot it (I live 500 miltes away) so I'm not sure if it stopped running when he was messing with things, or if it hadn't been running the whole time. Anyway, they sent it to me and I've tried troubleshooting it to no avail. When I first turned it on it got to the bootup screen before freezing. At this point I noticed the CPU speed was listed as 1100 Mhz. Now when I turn it on it doesn't show anything on the screen (what would cause this, a heat issue?) First I was getting a C1 error, so I tried switching out and trying to each memory stick individually. No luck. Eventually I ended up with a wide array of post codes, including: C1: Detect memory 26: Reserved 29: Program CPU internal MTRR, Initialize the APIC, Program early chipset, Measure CPU speed, Invoke video bios Sometimes it would boot up to 29 and then go back down to 26 It seems 95% certain to me that either the CPU or motherboard (or PSU?) has gone bad. Is this correct? If so, how can I find out which one it is so I don't buy the wrong thing? Thanks a lot.