Why not take that clue and run with it?
By now you know the big issue with the exposed core Athlons so I'll write it's either the CPU or the motherboard.
Bob
I have gotten into collecting, upgrading, rebuilding and selling old desktops. Its a good way to make a little extra cash as a university student. I have one that is puzzling me. I acquired an old PC from my cousin about six months ago with this ASUS motherboard. It was working fine until I tried to install a new processor. It is an ASUS A7N266-VM Motherboard. It had an AMD Athlon XP 1600+, and I tried to upgrade to an Athlon XP 2200+. I then read some threads and many said that nothing above a 1900+ is compatible with the board. I never got video at all, and just a siren type sound. I reinstalled the 1600+ and I still had no video, but the sound had gone away. After blogging I found that the sound was a DRAM error, so I tried all different combinations of 256MB PC2100, PC2700 and PC3200 with no luck. I was also told it could be low voltage, so I replaced the power supply with another one that had been tested. All the lights come on, HDD light comes on and off like normal, CD Drives boot, Keyboard boots, but no video. I was also told that to reset the CMOS you had to jump two points on the motherboard underneath the BIOS battery. This did not change, but now the siren sound is back even with the 1600+ I know it's an old Desktop, but I'm just trying to make a few bucks and give some people something simple to use. Is there anything else I can try? or should I just scrap this one for parts?

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