Computer shuts on and off

I have read quite a few of these but there never seems to be an answer. i just got the system in my sig in today, got it all put together running great. i was installing software on my computer and went to a random restart. when it goes to boot back up it comes on for about 3 seconds then shuts back off. i have tried to reseat the cpu, clear cmos, all power connectors r hooked up. does anyone know something im missing here? i really want to get to gaming!
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More about computer shuts
  1. Sounds like overheating or not enough power
  2. ok so i called gigabyte and they told me to start with just the mobo and and 1 item until i find the problem. well when i add the cpu it has the problem. however i dont know how i can tell if it still boots, since the cpu makes it restart. any ideas?
  3. does anyone have an idea i really want my computer :)
  4. In BIOS set the memory voltage to 2.1-2.v or Mfg. Specs. You will need to adjust the memory speed to PC8500 and set the memory timings also. Use one DIMM in slot 1. Ater you load the OS and MB system drivers, install the second DIMM.
  5. i cant get into the bios. it only comes on for 3 secs total.
  6. You likely have a short. Try unplugging everything except the CPU,1 DIMM RAM and the video card and boot the system with only CPU, RAM and video card and get to BIOS. The HD, optical drives, sound cards, etc., unplug it all. If the system still won't post, your MB may be shorting out the system. It likely a short OR a bad PSU.
  7. could it be the cpu? b\c as soon as i put the cpu in it cuts off and on.
  8. Do you have the 4/8 pin 12v power supply lead plugged to the MB supplying power to the CPU?
  9. See directly above.
  10. yes i have both and have tried them both.
  11. Have you smeared thermal paste on the CPU connectors? That would short out the CPU, if any TP is touching the 'pins' or 'socket'.
  12. the last time something came on screen was something about a bios updating or restoring. then it cut off and nothing would come up as it only came on for 3 seconds
  13. oh and no have havent gotten on any connectors, but ill double check
  14. Are you using the stock Intel haetsnk and fan that came with the Q6600? If so, you might check the mounting legs and be sure each leg is snapped firmly into place causing the heatsink to make complete contact with the CPU.
  15. BIOS on the screen? I think I would reset the CMOS jumper about now. In you MB manual...unplug the system from the wall, remove the battery and reset the CMOS jumper to default the BIOS.

    Did you try to update the BIOS already?
  16. im using a ultra 120 and i tightened it as far as the screws would allow me. i dont know if this is b\c the cpu wasnt all the way down or not, but i unlatched the cpu for just a sec to see if it would come on and it didnt cut off. i dont know if it booed or not though.
  17. ive reset the cmos several times to no avail.
  18. do i need to remove the batery as well as do the jumper?
  19. Did you fit the CPU in the 775 socket properly. It only fits properly one way. Instructions in the MB manual.
  20. yeah its in correctly
  21. Yeah, unplug, remove battery, reset jumper.
  22. ok let me go find a jumper ill brb
  23. when you mounted the MB, did you use the brass 'risers' that hold the board up elevated from the case chassis? i don't know, it sounds like you may have a short.
  24. ok so i did both and neither worked
  25. Q: the sytem was running. Then it shut down and refused to boot when loading software. Did you add any hardware betwwen the time it was running and the time it shut down? How about the video card? have you tried reseating it.
  26. yeah i used the risers. last time i was in the bios before it quit working i had to set the cpu volage. u think that might have messed up the cpu . i didnt set it high but i cant think of nething else. voltaage was 1.32
  27. have you tried each DIMM of RAM as a single in slot 1 since the system crashed?
  28. no i never changed any hardware, only cpu voltage
  29. yeah i only have 2 and i dont think they are boh bad, even if they were it should still go to bios. shouldnt it?
  30. 1.32 would not have been memory voltage. More likely CPU voltage. How high did you set it? Well, you made another socket 775 CPU to put in and see if the systems runs with a new processor. I have overvolted a CPU before, but I distinctly remember the smell.
  31. what measures ur temp for ur cpu, the reasonb i ask is while the system was running it was siting idle below 30 c
  32. Install a second socket 775 CPU and see if the system runs with it?
  33. could it be the pins on the mobo socket?
  34. It's down to pretty much swapping out the hardware and testing that way to find the problem.
  35. Well, thermal paste on those pins would short the system out. You could try a magnifying glass and look closely for damage if you think it is possible you damage the pins or socket.
  36. i have an old p4 2ghz. same socket?
  37. If it' 'old' it could be a socket 478. You could tell that by sight.
  38. yeah it wasnt 775 im thinking its the cpu, b\c thats what throws it off everytime. but i dont smell nething like i fried it
  39. What about the PSU? Is it new? Does it power on at all now?
  40. the psu is good i believe its a brand new cooler master 850
  41. Well, you might try taking the MB out of the case and trying to get it post with CPU, 1 DIMM RAM and the video card. Your description sounds to me like a short. If you set the CPU voltage too high in BIOS, resetting the CMOS jumper should reset that voltage to default too. It's pretty hard to burn up a CPU...unless you shorted it out somehow.
  42. ok i just took the memory out and while the 3 seconds its on the speakers beeps
  43. Besides trying the MB, CPU RAM and video card outside the case, the only option I see would be to start trying new CPU< RAM< video card, PSU, etc. I've been there. Shorts, fried systems overvolting them, hosed a BIOS update, and on and on. I have screwed one up in while though.
  44. Well, the MB knows there is no memory! That's a good sign it may be workable yet.
  45. how would a find a short?
  46. It could be the PSU. It's new, you had the system running for a short while and now it won't power up? If you have another PSU it's worth a try.
  47. it will power up it just wont go to the bios
  48. To find a short. Unplug EVERYTHING except the CPU + fan, 1 DIMM of RAM in slot 1 and video card. Boot and see if BIOS comes up. IF not, you would have to take the MB out of the case and set it on a cardboard box and try again with ONLY the CPU, RAM and video card. The system only need the CPU, RAM and video card to post BIOS.
  49. It powers up AND STAYS ON? Or it powers up for a sec or two and shuts down?
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