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CPU Red Led Light

Okay Ladies and Gentlemen,

Also, I am a new member to Tom's, but I always liked this site (especially since piracy isn't supported) :bounce:

I promise this has nothing to do with any product keys, activation, etc. (like some of the posts I have read). I have built my first computer. The problem is sometimes it will boot, with red cpu light on then flickers off; but other times the red cpu light just stays on, no boot, no bios, no post. I have looked at the check list posted here (first website I always go to). Everything is in working order, mobo is grounded. I'm generally confused. I ordered 2 more cpus just in case.
Well here's a list of my specs, please let me know what you guys think:

IN WIN Griffin Mid Tower (CASE)
HX750W Corsair (PSU)
Sabertooth 990FX R2.0 (MOB0)
16GB DDR3 Corsair Vengance (MEM)
AMD FX 8350 8 Core Processor (CPU)-Stock Heat Sync Fan ( I also have an aftermarket heat sync; just in case)
GeForce GT620 (Graphics Card)
ASUS CD/DVD Burner (Optical)
500GB HDD

So let me know what you guys and ladies think. Thank you very much for your time. :D
P.S. I have tried removing cmos battery plenty of times.
28 answers Last reply Best Answer
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  1. I might suggest checking the CPU for bent/missing pins, might as well put the aftermarket HSF on there at the same time. Don't forget to clean off the old thermal compound and apply fresh (if not pre-applied to the new HSF). See what you find there. I have read of missing pins on 8350's in the past few months, I suppose it could be that.
    Hope it helps
  2. no bent pins. I checked about 6 times (each time placing it in and out) it seems when I take out the cpu and put it back in. It works fine, but then the problems persists. Also, how would I clean off old thermal compound? And one other thing. for this mobo the couple times it booted, it stated that "current cpu cannot use asus core unlocker" would it be wise to install another cpu (the ones I ordered) when they get here?
  3. You could try another CPU, but I'm more inclined to suspect a problem with the CPU socket. If the new CPU does not resolve this issue, I'd RMA the board.
  4. should I do an external build again? This time with the After Market HSF?
    Also @ onus, so after trying another (when it comes in) by that time I should try to RMA?
  5. Also, How do I clean off the compound?
  6. Check your BIOS version - support for that CPU is version 1006 found here http://www.asus.com/Motherboard/SABERTOOTH_990FX_R20/#support_CPU you may need to flash to a newer BIOS.
    I'm beginning to suspect you may have 'cooked' your CPU. Replacing the thermal compound is highly recommended if removing the HSF. Amuffin did a fine thread (IMO) on cleaning and applying thermal compound here http://www.tomshardware.com/forum/333968-28-thermal-paste-removal-installation-guide I will recommend trying again (same CPU) after reading through that. edit: and getting thermal compound
  7. Best answer
    Hey USMC2010, sounds like you built a super nice system. The best way to diagnose this problem is to breadboard it to see if you have a working system. Or as you say, external build. To do this:
    -remove the motherboard from the case with the CPU and ram.
    - Place this on a piece of cardboard that is bigger than you motherboard.
    -Usually your MOBO box is the right size, so put it on that.
    -Attach the 12v 8 pin and the ATX 24 pin power connectors from your PSU.
    - You need to have a GPU in order to see what is on screen, so use an extra working GPU if you have one or mount and plug in power to your gt620.
    -Connect your monitor to this set-up.
    -at this point you should have your system, without anything connected to the SATA ports. Just ram, CPU, GPU and PSU.
    -Now attach a Keyboard only.
    -Use a flat heat screw driver to touch the +,- power pins on the MOBO.
    -If at this point if the system boots to the BIOS screen your main components are good.
    You can either try touching the pins again to turn off your system or flip the switch on the PSU to turn it off.

    If the above works, check your case stand off screws, the little brass screws that go between the case and mobo to see if they all line up with holes on your mobo. If there is one extra screw you could have the problems you are seeing. Check to see if there are any exposed or cut wires on your case fans.

    When you say you grounded your MOBO, how did you do that? Typically the MOBO's circuitry is grounded through your PSU. You don't want any of the electronic components to ground to your case.

    If the above doesn't work try booting with just one stick of ram. Like I said before, try also getting another cheap or known working GPU and test again. By doing this we can eliminate some possible issues and narrow down the component causing problems for RMA.
  8. C12 got in before me. I disagree that it is the thermal compound. I have run computers with a dry heat sink, usually the system will switch off as soon as the components get too hot. The only time I have cooked a CPU is when the PSU failed and over volted the system. You can try replacing the thermal compound but this will not fix your issue. It will be good once it works but we should focus on getting it running first.
  9. update.
    External build. Passed. CPU led light came on, but then switched quickly to boot. I am looking at bios utility now. of course the "system does not support current boot..." came up. But I did try what adamv1 said. Everything turned on, with 2 sticks of ram. gpu card. stock cpu heat sync fan. cpu. and 2 power connectors plugged in.
    Question though, when you screw the screws for the stand offs. is it the flat part touching the board or do you screw from the back and it comes straight out (straight part) through mobo
  10. just tried to turn it on again via flat heat screw driver. but cpu led light stays steady on red
  11. Pressed the MEM OK! button on mobo. and it booted up and cpu led light came off
  12. I think I understand what you said. When you screw in the stand off, the threaded part of the stand off should go into the case leaving the flat part of the stand off facing the motherboard. The motherboard then lay's on those standoffs with a female screw hole lining up with the holes in the mobo. Then take the screws that fit into the standoff female holes and attach the motherboard. Be sure you only have enough standoffs for the amount of motherboard mounting holes present.

    I think we are very close to having this problem solved. If bread boarding worked we can assume your components are good. It is your case assembly causing the issue.
  13. USmc2010 said:
    just tried to turn it on again via flat heat screw driver. but cpu led light stays steady on red


    When this happened was it related to the Memory? You said you ran it with two sticks before and it worked, did you run it with more and experience an issue?
  14. no ran everything the same. actually, it was my fault. turned off the power tried it again, but this time i forgot to turn on the power switch. so the problem currently is my display in the case correct? maybe I don't understand how to screw in the stand offs. I
  15. I searched google and found these nice pictures that might help.
    http://m.kitchentablecomputers.com/assemble3.php

    It will walk you through the assembly process as well. It's a little old, I have never seen the other two case standoffs he has in the pictures, just the brass hex.
    hope that helps.
  16. Okay I looked over the article. It ACTUALLY does help a lot. Thank you for taking the time to look up a link for me. The last question I have and wasn't answered by the article, was I only have 2 stand offs. is this normal?
  17. No, you should have more than that. The motherboard you have will need at least 6 to be firmly attached. This could be your problem. I bet the MOBO is bending enough to touch the case causing a short. Usually the Case comes with more than enough stand offs to fill all the holes. You should get all the MOBO screws in the front and middle attached. The ones in the back, the side with the 24 pin connector are not essential, but if you can I would attach them. That would make 9 stand offs for your MOBO.
  18. Then from what you just told me. I believe that is the problem. I only have 2 stand offs from the screws that came with the case.
  19. Since, that is the case, do you happen to know if fry's or an electronics store, etc. has stand offs that I can go purchase?
  20. I would call IN WINN and let them know they robbed you of at least 7 screws. If you want to get them quick I'm sure a pc repair shop will have some on hand. I have thousands of them cause most cases come with extra. But that is definitely your problem. Get that fixed and you should be good to go.

    Good luck.
  21. Also, since we resolved this issue at hand. I have an additional questions. 1) Should I install my After Market HSF?
  22. Thank you very much adamv1!
  23. USmc2010 said:
    Since, that is the case, do you happen to know if fry's or an electronics store, etc. has stand offs that I can go purchase?


    I wish I had a fry's near by. Yes they will have them, way more than you need. If you got the case there, tell them that it didn't have the parts you needed in it and they should give you some for free.
  24. Thank you again
  25. Best answer selected by USMC2010.
  26. USmc2010 said:
    Also, since we resolved this issue at hand. I have an additional questions. 1) Should I install my After Market HSF?


    IF you got one then go for it. Use alcohol and a cotton bandage to clean the CPU, clean the edge of the cpu with a q-tip. DO NOT TOUCH THE PINS ON THE BOTTOM. Then apply a light amount of thermal paste. I wouldn't recommend doing this without reading a little bit about how to do it properly. There are allot of way's to do it right and allot of ways to do it wrong. So take a minute to watch a video or look at some pictures of someone else doing it before you try.
  27. Got it. Thank you
  28. Thank you USMC, Semper fi marine. And good luck.
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