PC shutting down before bootup

So, I built a PC about 3 years ago and it worked fine until about 5 months ago. It started randomly shutting down for no reason. After a while, it would shut down after being on for about 45sec or less. At first I thought it was a virus or something, but according to all of the virus and spy/ad/malware scans it’s clean. I uninstalled each component down to just the mobo and the PSU and tried to power up after each was removed and I still had the same problem. Since I couldn’t figure it out, I just got a new mobo and installed it. It worked up until about a month ago and then started shutting down not even a minute after trying to boot up.

I then gave the PC a thorough cleaning thinking that would solve the problem but it didn’t. I have since replaced the RAM and that didn’t fix it. I thought the PSU was the problem so I got a new one and installed it today. That didn’t fix it. I just uninstalled everything one at a time trying to power it up after each component was removed again and it’s still doing the same thing.

Does anyone have any idea of what is going on?

[SIZE=3]Intel Core 2 Quad Q6600 Kentsfield 2.4GHz 2 x 4MB L2 Cache LGA 775 Quad-Core Processor[/SIZE]

[SIZE=3]ASUS P5K WS LGA 775 Intel P35 ATX Intel Motherboard[/SIZE]

[SIZE=3]OCZ Platinum 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory[/SIZE]

[SIZE=3]XFX PVT98FYDF9 GeForce 9800 GTX(G92) 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card[/SIZE]

Antec 550 Watt PSU

Parts swap:
[SIZE=3]ASUS P5N-D Motherboard - NVIDIA nForce 750i SLI, Socket 775, ATX, Audio, PCI Express 2.0, Gigabit LAN, S/PDIF, USB 2.0, Firewire, Serial ATA, RAID[/SIZE]


[SIZE=3]G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory[/SIZE]

Have you checked the temperature. Last time we saw something like that happen it was due to an overheating processor.

Could it really overheat that fast? I put a decent amount of thermal paste on it. I try to make sure I put enough on so that there isn’t any over spill when I had the CPU fan. I use about a half pea sized amount.


@ OmNiExiTz, I saw no mention of fans in your system. You might need to review your PC cooling system.

Did you check the fan?

I didn’t think that mentioning the fans were important. But I have 4 120mm fan with adjustable speeds, so it’s stays pretty cool I’m sure. I haven’t overclocked anything, so heat shouldn’t be a problem. The fan processor is stock. My case is the antec P180.

But have you checked the actual core temp? Because everything you described seems to indicate that the processor is overheating.

Ok, I know this is going to sound crazy, but I have no idea of how to check the core temperature. The only way I knew of to monitor it was in the BIOS and I can’t even get to that. Is there some kind of test kit I should have?

Check the fan if it’s still “stuck” on to the processor properly, check for dust or even if it’s just spinning.

Other than the overheat issue, the only other problem I can think of that there’s either something wrong with the mobo or processor.

You also want to look into the actual air flow in your PC case.
Having a quality fan means nothing if air isn’t getting to the parts that need it.

Also check to see which way all the fans are blowing.

Besides for the CPU and video card fans, you would want a Push-Pull metion of air cooling.
Fans in the front and side are pulling in colder air from the room and fans in the back and top are pushing the air out

Just like the picture provided

Keep in mind heat rises, so you want to get your air from front of the PC case and down low, and the hot air blows out the back and up

Also never recirculate hot air

Hmm…something could possible be fried on your mother board. Im not an expert on the subject but go to: beyourownit.com, and go to the forum section. They are really, really good when it comes to answering these type of questions.

My last computer, which was not a custom build, would shut down as soon as it left the black boot up screen. Similar to you I tested many parts of my system in steps and in the end went out and bought another mother board and that solved the problem. It should be noted that everthing from my old system: Ram, CPU, cards, etc worked fine and the mobo (mother board) only costed like $50.00. Again the problem you have is probably fixable, check out the above mentioned site your sure to get help there.

Well, I can rule out the cpu overheating. I’ve got good airflow because I setup the fans using the case instructions. I also turned it on to see the temp and it’s around 32C/80F. The only way I could get it under that would be to get a larger heatsink. isn’t there someway can turn off the overheating safety feature? I think that might be the problem. My house stays pretty cool, so I really don’t see how heat is the problem. And I’ll be damned if I’m going to get another mobo considering I’m having the same exact problem with this “new” one. It’s also getting harder to find a decent mobo to support my components and keep the same features for a reasonable price as seeing how my original one which was top tier at the time is phased out. Or unreasonably priced.

My guess is the video card, it very well could be overheating, or it could be shot from overheating. You don’t overclock, but even under full load your video card will not go over 30% fan speed, I’ve had my card hit 70C on idle because it was at 10% fan. See if your video card fan spins if not do you have an older card you can try?

By the way, does your PC make any beeping when you try to turn it on? This could help me uncover your problem.

If you can get your PC all the way on, download EVGA Percision(it works will all Nvidia cards) and set the fan speed to 100%(uncheck auto and move the slider all the way up) and apply it.

Nah, it can’t be the video card. Like I said, I’ve had it down to just the mobo and processor and it still cuts off after about a minute. I’m not getting any beeps before it cuts.

Want to test your luck on another processor? That would almost have to be it.

I guess your PC doesn’t have a beeper, which is rare.

It does, I had to install the speaker separate though. Like I said, it boots up, but shuts down after a minute of being on. I only get the one beep during post but that’s it. I’ve disconnected my hdd so my data wouldn’t get corrupted. I’ve never had a processor go out on me, but there’s a first time for everything. If I can’t get this thing working I’m upgrading to a sandy bridge i5 and a Asus p8p67 deluxe.

Just upgrade if you are already planning on it. I am not a big intel fan(too expensive) but the new i5’s are impressive.

Have you tried using a different PSU?

A complete power down really sounds like a PSU issue to me. Check the voltages in BIOS.

Yep, I’m on my second PSU now and I know that’s not the problem. I have PSU tester that I’ve used in the past and everything checked out ok. But even though I changed to a new one (just got it yesterday) my machine is still giving me the same problem.

Hmm, all I can say is check if everything is seated properly, like your 24pin or 4/8 pin on the mobo, reseat your heatsink, clear cmos and try booting with only one stick of RAM. Oh and check for blown capacitors on the mobo.