Issue with older P4 desktop - boots ~1/20 times

[Shawn]

I am fixing a P4 3.0Ghz desktop for someone. He initially brought it to me because it had a virus. I was planning on just reinstalling the OS for him.

However, when I went to boot it up it kept freezing before it loaded the OS. It was also freezing randomly in the BIOS. I noticed that the CPU was overheating so I took off the CPU and discovered about half a tube of Arctic Silver on the HSF . So I cleaned it off, applied the correct amount and removed a crapload of dust from the heatsink which was blocking airflow.

Computer seemed to work fine on next boot and I reinstalled windows. No issues until restart. However once it restarted it started freezing again. I went into BIOS and CPU temps are normal. Only difference is now it's not freezing in the BIOS.

I took out all the PCI cards and still freezing, swapped out the video card and still freezing. Disconnected the hard drive and cd drives and still freezing. It freezes after POST but before it gets to the point where it boots from a device so it won't boot from a CD either, even with the hard drive disconnected. Reset CMOS, Rearranged ram, tried only one stick, and still freezing.

Then randomly on one try it booted and completed the windows install. Ran windows updates and restarted and wouldn't boot again.

I don't know whats going on but I'm not sure what is wrong. It will eventually boot if I keep powering on and off. Once it's in windows it's stable and won't have issues again until next reboot.

I'm thinking maybe the mobo is going bad but I have no clue. Next thing I'm going to try is swapping out the PSU.

 

[C1]

I would pull the memory sticks, vacuum the slots and clean the stick contacts with Deoxit before reseating them. Also, clean/reseat all other connectors to the MB.

As a last resort, pull the MB & PSU from the case and try to run the system open (on a table using an insulator such as cardboard). This eliminates any MB short to the case.

 

[Shawn]

Well I think I've got it figured out. For whatever reason it works fine once I disconnect my USB keyboard. I tried a different USB keyboard and same problem. If I leave it unplugged it boots fine.

 

[denis280]

Have you try PS/2 connection if you have one.

 

[Shawn]

I don't have a PS/2 keyboard, but I was able to get into the BIOS long enough to disable halt on errors and disable USB legacy mode. It now boots fine into windows with the keyboard connected.

 

[musty989]

I have a slightly similar problem that I actually just posted about as well. For me my computer restarts just fine, it's when I shut it down or turn it off that I have problems getting it to start up. When I hit the power button it just doesnt start up, no fans, or post or anything but a faint yellow light on the mobo that blinks fast like it's waiting for something to happen. I'll have to turn off the psu and back on and keep trying to power it up, eventually it'll turn on and be just fine but it can take 2-15 trys, it's so random and weird idk. In the past when I has a usb webcam attached if I tried to power up and the problem happened, sometimes (not all the time) when i removed the usb cord it started up, and I as well have a usb mouse and keyboard but even when trying without those plugged in I still get the problem. I'm stumped! lol