athlon xp 2800 + asus a7n8x deluxe = no boot! HELP!

So I recently got an Athlon XP+ 2800 and put it in my asus a7n8x deluxe motherboard. I power on and fans start to spin, but the monitor led stays yellow, and then seconds later it turns off. I knew the processor wasn't dead because a. I just bought it and b. I put it in an old syntax board and could boot up fine (only at 1.6 ghz because the motherboard doesn't support 166fsb). I tried clearing the CMOS on the a7n8x deluxe. Same problem. I set the fsb to 100 and put in an old Duron 600mhz processor I have and it boot up fine. So motherboard should not be a problem. CPU should not be the problem. The RAM is 1.5 GB of PC2700 so that should not be a problem. WHAT'S THE PROBLEM?!

If I have no CPU installed the computer will run the fans, power up, leds, etc. and stay on. No picture on monitor, but it doesn't shut down either. A bad CPU I have would do the same thing. A good CPU boots... but this CPU starts and shuts down. Can't be overheating either since I tried it in the other and I doubt it would overheat at the same place everytime before getting any kind of response. Heatsink and fan are definitely in place. I'm trying to give as much detail as I can. I've tried resetting the CMOS twice now and it hasn't worked.

PLEASE help! I can't afford to buy another CPU or mobo right now. I'M DESPERATE FOR HELP!

 

What power supply do you have? Make and model.

 

does the power supply matter? I have similar problems with a lower end setup, all the fans work but nothing really 'works'. I thought since the fans spin that there is enough power and it's just hardware prob after that.

 

i don't think its the PSU try removing and reinserting the graphics card then try removing and reinserting the RAM

 

hope this is not your problem but you never know.

had the same problem a while ago and kicked myself after worrying about it for an age, i had placed the CPU fan on the wrong way round and it was not touching the cpu properly, (it fried the cpu) it overheated and shut down after two or three seconds, the socket A fans only go on one way, i checked this with a new cpu and heat paste to see if it left a print on the fan once it was correct i cleaned the new cpu and heatsink, re pasted and fitted problem solved, (god i felt dense) i hope its as easy as this for you, overlooking the obvious is my mistake, i wont happen again. regards and good luck Jadedhills

 

So the computer is running but the screen doesn't display? Is that it?

 

right, remove your gfx driver use the "Standard VGA" driver (display properties) then reboot & reinstall drivers