Computer Help - PC Boots for 5 seconds and shuts off

[Solecord]

This evening I took apart my computer to give it a nice good clean as there was tons of dust in the heatsinks, cpu fan, case fans, etc. After putting everything back together when I go to start it up the case lights and fans turn on for about 5 seconds and then everything shuts off. If I take off the heatsink/cpu fan, do I need to reapply thermal grease? I did read on one site that if you take the heatsink off you'll have to remove what grease is left and reapply new stuff. Is this true? Any other ideas as to what's going on?

[Phenom]

I'm betting your CPU is probably overheating, try getting some Arctic Silver and maybe spending some money on a decent heatsink if you don't have one.

If you took the Heatsink off the CPU and then re-installed it you probably created a hotspot on the CPU surface where the thermal grease was spread to thin. You should apply about a paper thin layer of thermal grease to your CPU, set your heatsink, and try not to budge the heatsink once it makes contact with the CPU's surface.

gl

[Solecord]

What do you apply the grease with? Are there any big box retailers who carry the grease? (edit >> just saw Radio Shack sells it)

[Zop]

I would think overheating would take a bit longer if the heatsink is still touching, at least. If the grease doesn't work, disconnect everything but RAM and CPU to see if it will stay on, then try video card to get video, and so on with everything.

[Phenom]

What do you apply the grease with? Are there any big box retailers who carry the grease? (edit >> just saw Radio Shack sells it)

Also try what Zop suggested.

As for how to apply thermal grease, I prefer to use a razor, a credit card or card of any thing relative that can help you guide a thin layer over your CPU chip. Remember don't glop the shit on either, the last thing you want especially if your going to use Artic Silver is for it to make a connection to your CPU's pin connectors. If you make a mess, using denatured alcohol on the end of a Q-tip cleans Arctic silver/grease up nicely and the alcohol evaporates pretty quick once its rubbed on.

If that doesn't work, try Zop's method.

I would disconnect EVERYTHING but the CPU. (e.g. Ram, harddrives, AGP, PCI cards ect...) if the PC stays on then add ram and retry, if it stays on add your video card back and so on, one piece at a time, this will help you diagnose which piece of hardware might be the culprit.

Hope this helps!

*Note make sure your motherboard isn't grounded by chance even though it doesn't sound like its grounded to the case. If it was you'd probably be roasting marshmallows instead of posting here

the computer's priority is CPU> ram>videocard>harddrive>PCI cards.

without ram, you'll be able to turn your PC on, but you might hear a beeping sound and experience a blank screen. Once you add CPU+ram your pc should be able to at least get to BIOS post but no video (no video card yet). just try each piece out and make sure your hardware isn't defective.

[Fuzznut]

I had the same problem. CPU fan went out. upon bootup mobo detected no fan running and shut down to protect the cpu. try checking your power connection to your cpu fan.

[Fuzznut]

Well you say the cpu fan is still working? Probably what zop and rook said then.

[foq]

yes, if you take the heatsink off, you should clean off the old paste and re-apply new stuff. I put a small amount on the cpu and spread it out with a sandwich baggie, then re-install the processor, and put the heatsink on. Clean both the heatsink and the processor, apply thermal paste to the processor only.

Perhaps you got something loose somehow. As the others said, overheating doesn't take 5 seconds... at least from a cold boot. I would try unplugging the comp, draining the power (press and hold on button for a few seconds while unplugged), and re-seat everything. RAM, video card, any other plug-in cards you may have, disconnect and reconnect all the power cords and cables...

[Solecord]

Well it appears when I did each piece of hardware one at a time, the floppy drive was the culprit. There's the floppy ribbon that goes from the drive to the mb and then there's another wire coming off it that (that is similar to the speaker and power plug that got stuck in the mb - sorry I don't know all the lingo lol). On one of the plug it says DATA+, DATA-, and GND. I don't remember where that was plugged into so perhaps leaving that out or not plugging it in to the right spot was causing the PC to turn off??? When I leave the drive off the computer boots up and runs fine.

Any info on the floppy drive? The drive is a floppy and 8-in-1 media card reader. I have no instruction manual or anything with the drive, it just came with the pc.

[Phenom]

On one of the plug it says DATA+, DATA-, and GND. I don't remember where that was plugged into so perhaps leaving that out or not plugging it in to the right spot was causing the PC to turn off??? When I leave the drive off the computer boots up and runs fine.

Any info on the floppy drive? The drive is a floppy and 8-in-1 media card reader. I have no instruction manual or anything with the drive, it just came with the pc.

On your motherboard there should be a group of tiny pins, if you look very closely around the motherboard where those pins are located you might see that the pins are labeled DATA+ DATA- & GND.

These are usually located on the bottom right side of your motherboard.

[Solecord]

I did not see any pins labeled DATA or GND. If I do not plug that in but I plug in the ribbon, would the system not boot up? Could the ribbon be bad? I don't know if I have a spare ribbon around to test that. I'll have to look.

[Phenom]

I did not see any pins labeled DATA or GND. If I do not plug that in but I plug in the ribbon, would the system not boot up? Could the ribbon be bad? I don't know if I have a spare ribbon around to test that. I'll have to look.

IDE ribbons should not prevent your PC from starting, they will prevent harddrives/floppy drived from transfering data since thats what IDE cables are fore

[Solecord]

Well anyways I removed the floppy drive since I never use it anyways. I booted the PC up and it gave a message that said it couldn't boot because of a POST failure (I assume from turning it on and off when testing each piece of hardware). I went through bios and made sure everything was set right and rebooted again. This time it said DISK ERROR and could not load the OS. I realized I had the harddrives plugged in the wrong order (I had my 3rd drive plugged into the 1st slot, and so on). I rearranged them to the proper order, rebooted, loaded Windows in safe mode and about 3 minutes in the computer just shut off. I left the system off for about 20 minutes (because I had to go move my car lol) came back and turned it on again. Windows loaded fine this time, however after the desktop loads a blue screen pops up and the system reboots. Any ideas? I can't read the error because the system reboots right away? I'm going to try reseating my RAM but I dunno?

[Solecord]

I reset my RAM and when I reboot it now comes up and says something about a Windows file is missing and I need to repair Windows. It'll reboot after that but then it kinda locks up and doesn't reload. It comes to the screen telling me the graphics card info, and then either locks up there or it pulls up the bios verison and then locks up there.

[Phenom]

Make sure all your fans are spinning, all connections are secure, also watch your temperatures in your BIOS to see if any over heating is happening with your CPU/PSU if you can.