Motherboard or Cpu at fault? New build acting strange?

Hello, Everyone-

I am sorry to bother you guys, but I need some advice. I recently put together a pc with these specs:

PSU: Cooler Master 600w
Video Card: BFG 8800gt

I built the computer last week and it worked flawlessly until yesterday. I had purchased an aftermarket cpu heatsink (Cooler Master Hyper) and wanted to intall it. I unplugged the PSU and removed the stock HS. I had to push down on the MB extremely hard to get the new HS pins to snap into place and that kind of scared me in the first place. I know I should have taken the MB out first, but I was too excited to get the NEW part installed. Finally, after fighting with the HS I was ready to reattach everything and see my new temps. I actually told my wife, who was sitting next to me that "wouldn't it be funny if it didn't start?" And of course it would not boot/post or beep. The cpu, video card and case fans would spin for a split second and then stop. The lights attached to the case would turn on and off at the same time as the fans. The monitor never came on or anything.
I then disconnected everything and tried turning on the machine with each device attached on at a time and I always got the same results.
I removed the MB and took it to my workbench and connected everything on at a time again, and nothing different would happen. I switched memory and tried every slot and combination thereof. Still no posting/booting or beeping, just fans that would do little more than twitch. I tested the psu and video card in another pc and they worked fine.
I reset the bios by both jumping and removing the battery....nothing
I started messing with the 20+4 pin and 4 pin cpu power connector and discovered that if the 4 pin cpu power connector was NOT plugged in, the fans would continue to spin, but the pc would still not post or beep. If the 4 pin connector was plugged in then the fans would only start to spin and then stop. I also discovered that I could actually get the fans to stay on with the 4 pin connector attached if I pressed the on/off button repeatedly before the fans would slow down. It was like I was giving the fans a step input and they would continue to spin if I pushed the button at the right times?????
I have searched and searched for another case like this but, I can only seem to find issues with this motherboard that come about because of bad memory, but not like this. What do you guys think. I also took a pentium 4 (R) processor out of my old dell 4700 and put it in the Gigabyte MB and I got the same exact results I don't know if that spare cpu is compatible though?
I am hoping that the MB is to blame, b/c it can be returned. Does this sound like a CPU problem????:(
1 answer Last reply
More about motherboard fault build acting strange
  1. I have a problem very similar to this. I didnt want to start a new thread because it seems like the OP did a good job describing the situation. When the 4 pin connector is unplugged from my computer it runs but nothing shows up on screen but when it is connected the computer will turn on for a second and immediately *** down.

    Please someone help me out with this I'm in school and desperately need my comp up and running ASAP!! Thanks.

Ask a new question

Read More

Motherboards CPUs