Computer Boot Then Shuts Off and Repeats!

After building my computer (first build btw), it has had problems when starting up. Ever since I have built this rig it has happened and the problem is different every time it happens.

Every exact thing that happens when I turn the computer on is: I press the power button and the lights on the front and in the LED fans come on. Also, the fans spin and the hard drive starts to turn. The graphics/video card's fan starts out fast and loud but after about a half a second, it slows down to, what i can guess is, a normal speed.
I have opened the case to watch everything and one thing that caught my eye was the CPU cooler. The fans starts once I hit the button, but after about a second, it stalls, then instantly catches again. Other times the fan wont come back on because sometimes at this point, this is when the computer will turn off. Otherwise, it will catch for a bit then turn off. During this process, I cannot see the BIOS, the screen is black. After staying off for about 3-4 seconds. it will start this process again and might repeat or (this is where I am completely confused) IT WILL BOOT! Yes, the computer will boot like it was just turned on. The amount of time that it will go through this process is completely random. As I type this message, I am using this rig. There is not a problem when i restart from windows but when i turn it off and try to restart after it being off, this happens. I have had a couple of lucky times that when I turn it off and then right back on (not a restart) it will boot.

The Specs for this system are as follows:

CPU: Intel Core 2 Quad Q9550 clocked at 2.83GHz (stock) E0
Motherboard: Gigabyte GA-EX38-DS4 with F6c BIOS (mobo is used from a friends rig, but was assured it worked)
RAM: 4 GB DDR2 Patriot Vipers Model PV224G8500ELKB 1066, 5-5-5-15, 2.1 volts
CPU cooler: Arctic Freezer 7 Pro
Graphics Card: XFX ATI Radeon 4890 Model HD-489A-ZDFC
PSU: OCZ ModXstream PRO Model OCZ700MXSP
Hard Drive: Western Digital Green 500GB
OS: Windows 7 RC Build 7100
Case: Thermaltake Strike MX Model VI6001BNS w/ 2 120mm one front one back
iPod when Computer Stays on... But not on startup

I have done the following to try to fix it
1. Update the BIOS to the Latest that GIGABYTE has to offer
2. Reset the CMOS (just took battery out....)
3. Ran with one Stick of RAM

Anything that might be able to solve this EXTREMELY frustrating problem would be just Fantastic!!!
11 answers Last reply Best Answer
More about computer boot shuts repeats
  1. Your RAM is rated to run at 1066MHz with 5-5-5-15 timings at 2.1v. Have you manually set the RAM to those specs in the BIOS? It sounds like the motherboard is failing to POST the first time and having to reset to safe settings in order to POST successfully. Incorrect RAM settings is a pretty common cause of that behavior. Have you run Memtest86+ overnight to test for RAM errors?
  2. I have manually set the timings and the voltage was already correct, but I have not run Memtest86+. I will try that tonight, thank you
  3. Ran Memtest86+ and reset the CMOS. It came back with no errors, but the problem is still here and I think it is getting worse. It took a lot of tries to get it to start and Now I got a message saying that there was a post error. I couldn't read it all but I got selected "Last Known Boot" or something like that. So I don't think that the RAM is the problem.
  4. can you try a different PSU?
  5. I don't have an extra PSU that I can use, but I am thinking about RMAing the one I have because I have a feeling that this one has something wrong with it.
  6. Great post!


    Your description does sound like a faulty PSU that is sending out a ready signal before it is fully warmed up.
  7. Best answer
    If you have a modular PSU then you could try swaping the cable that you used to connect the CPU fan for another one :). If that doesn't work then you would probably need a new PSU. Or you could try new intake/exhaust fans, you might have one of them running backwards pushing the hot air back inside the case and make the pc falter.
  8. I think I'm going to RMA my PSU to OCZ. I did take all of my cable out of there cable management formation (neatly tucked in the back and stuff) so now the are kinda just dangling in the extra bay slots. But, here is the good news, my PC only takes about 1 reset to start!! I'm thinking there is a fault in the 8-pin to the CPU. I had it tucked away and those symptoms were happening. But now it is just going straight there and it is doing better. Sometime it will even start on the first boot. so from what I can see here, there is a problem with the 8-Pin having a short or something like that. So, what do you guys think?

    new I should have bought the Corsair.........
  9. PSUs can get damaged in shipping, I've even had to RMA a Corsair PSU, but I still really like their stuff.
  10. Yep, I think we solved this one, thank for all of the help!!!! Will be RMAing ASAP.
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