Rig death...??

[Kong]

I've got an old custom built PC my kids use, I swapped 2 60mm fans, one was part of the cooler for the CPU, but it was simply unscrew 4 screws, remove fan, put on new one. I clean out A LOT of dust bunnies. I turn it on and it works but there is a strange burning smell, I assume it's just some of the dust. I turn it off after about 10 minutes. Few days later turn it on and am getting no video signal, same burning smell. I swap vid cards and no difference. The MB is showing it has power, the hard drive is spooling up, all fans are working, it appears to be running fine. Yes I doubled check to make sure the montior cable is connected securely.

Any suggestions how I can trouble shoot what the problem is??

Asus A7V133
Athlon 1400
512 Megs Ram
Gainward DDR Vid Card

 

[Arcygenical]

I'm having EXACTLY the same problem with an A8N-SLI...