Computer won't stay on long enough to boot

[drashleyscully]

I've been having a whole lot of problem with my computer and I've run out of ideas on getting it up and running. I just built it in July, I'm running a 3gig Pentium D. (I don't recall the type of motherboard or GPU, sorry. I can look it up when I get a chance if it is important). The computer worked perfectly until about a week ago. It started freezing up or going to sleep and not waking back up. I did an antivirus scan and searched for spyware at the time and nothing came up.
I loaned my computer to a friend for the weekend, but when I set it up for her at her house, it wouldn't turn on for more than a couple seconds. It started up and sounded normal, but then would just shut off. I took off the case and poked around and noticed the fan in my PSU wasn't spinning. So I went out and bought a new PSU, an Antec 430w (I had been using an antec 350w). I'm still having the same problem. After the computer shuts off, there is still power to the motherboard because the LED on it is still lit. The new PSU seems to be working great, i checked the fan it in and all my other fans. I checked all my connections and all my cards and the memory to be sure they are seated fine.
If anyone can offer me some suggestions, I'd appreciate it.

Thanks!

Ashley

 

[LipsOfVenom]

i had the same problem...i'm also using a Pentium D 3 Ghz...when i moved the computer to a different room, my heatsink and CPU fan got a bit loose from the motherboard so i could only boot the computer for...10 seconds before it heated up to 100 degrees Celcius, which is automatic shutdown temp for most computers. so thats the only thing i can think of...you're CPU fan might be a little loose, you really have to push those pins hard...stupid Intel fans...for $260 you think they'd give a better fan...oh well....hope this helps.

 

[kirock]

I think Lips is correct, it really sounds like CPU overheating. 3GHz P4 produce 100+Watts of heat and can overheat in seconds if the fan stops working or the thermal contact between the heatsink and chip die goes faulty. Carefully remove the heatsink/fan assembly, clean off any old thermal paste with a dry cotton cloth. REAPPLY fresh thermal paste!(caps are on purpose) Reattach heatsink/fan. ArticSilver is the best, but really any thermal paste will do. Radioshack/electronics store or any local PC store should have some. Ask for Thermal Compound.

Good luck.
PS. Be very careful removing and installing the heatsink/fan. Any undo pressure on the CPU die could result in CPU death.