Not expecting this to be an easy fix...

Solarjetman on 30/5/2009 at 01:24

Hi there,

I've been having a bit of trouble with the following rig, it won't enter POST and there are no bios beeps.

Rig
ASUS P5N32 SLI PREMIUM WIFI motherboard
Intel Core 2 Duo E6400 / 2.13 GHz processor
XFX GeForce 7600GT XXX Edition x2 SLI
Vista x64 Home Premium
Corsair DDR2 Dominator 2x1GB PC6400 (800) DHX RAM
Seagate Barracuda 7200.10 - hard drive - 250 GB - SATA-300
Plextor PX-760A - DVD±RW
Gigabyte GZ-X1 case

History
I've had the rig 2 years. In October 08 the old 650W silverstone PSU shorted out (found dead rig at home and fuse blown). The damage took out my keyboard too, but it seemed all else had escaped unscathed. The replacement PSU (VX 550W Corsair) showed no faltering. Then in April 09 the computer turned off suddenly mid Team Fortress 2. I assumed this was the PSU failsafe but had no idea why.

After this I noted significant reduction in performance during games. Three days ago I decided to get to the bottom of it, updating to Forceware driver 185.85, then, when this failed, tuning some bios power settings to the PCI-E slot (PEG). The result was the POST would not run and would not move to the bios, the DVD drive would click oddly and the harddrive would not access. Suspecting the PSU I removed power to the DVD and hard drive and also removed the second 7600 card. The POST ran with a beep and 3 bips and no display output. Blindly entering the bios and resetting it to default, the reboot awarded me with a display output. Reconnecting the DVD, HD and second graphics card the system started like dream. A quick test of performance showed it was working fine again. Next morning it was also fine. Then returning after work today the computer would not enter POST.

I've tried removing excess power sources as before, including case fans, USB etc. Also tried clearing the RCT RAM via jumpers and battery removal. No success; same clicking on DVD drive, no HD access, no bios beeps.

I'm now at the end of my knowledge and don't have the componants availible to swap out. The last thing I tried was using a Radion x1900 graphics card instead of nvidia, but to no avail, same result. It seemed like the right time to seek some help.

Working hypothesi:
PSU failing (light on motherboard is present however and all fans come on, including those on graphics cards)
Motherboard toasted (wouldn't surprise me, may have been the cause of the first PSU failure?)
CMOS RCT RAM battery has failed (that would be an easy thing to fix...)

Let me know what you think

Solar

Ladron De La Noche on 30/5/2009 at 03:06

PSU (Corasair PSUs have glowing reviews for stability and efficiency plus you have replaced the previous blown PSU.)

CMOS Battery ($3 tops at local Radio Shack)

Mobo (likely culprit, probably damaged by previous PSU)

Not familiar with Intel Mobos, unable to recommend a similar model to your ASUS SLI mobo. Here are the specs. (http://usa.asus.com/products.aspx?modelmenu=2&model=1325&l1=3&l2=11&l3=337&l4=0) click

Good luck. :)

Test your power supply with these tools. (http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=power+supply+tester&x=0&y=0) click

Solarjetman on 30/5/2009 at 09:50

Thanks Ladron,

Had a look around. Many are finding similar problem with mobo. Some suggest problems with (http://www.tomshardware.co.uk/forum/page-245117_12_0.html) RAM, others recommending (http://www.tomshardware.co.uk/forum/page-196878_12_0.html) CMOS reboot. One also suggested reapplying thermal paste to the (http://www.daniweb.com/forums/thread102709.html#) CPU.

As the rig has been working for a while I'm pretty convinced its the mobo or perhaps now the themal paste.

Ordered CMOS battery just to check but don't hold much hope. May try a different ram if I can get hold of one, swapping around the ones I have didn't help though. After that paste and the entertainment of a new motherboard.

Anyone have any suggestions for a good mobo?

Ladron De La Noche on 30/5/2009 at 10:50

Resetting the cpu heatsink is a good suggestion. Perhaps it has become loose during use, make sure it is properly seated and firm, apply a new coat of paste over the cleaned cpu core.

You can check your RAM with Memtest86+. Check each ram module individually, one pass is good enough on the test per module. (http://www.memtest.org/) click

I'm not sure the ram tests will be reliable with your present mobo so take that into consideration when testing.

I'm also dealing with a mysterious laptop computer problem concerning the lcd display. Frustrating to say the least but fun to solve. hehe :p

bikerdude on 30/5/2009 at 14:51

Its very lickly the ram, it has nothing to do with wither the cpu heatsink is on correctly or not..(the heatsink issue would only be noticable when the pc has been on for a while as it would shut down due to the cpu over heating)

Solarjetman on 30/5/2009 at 15:39

Seems possible it is the RAM, although system was running fine the day before. That said the bios was set to default and I never got around to setting the ram clock speeds manually (which I had done previously from day one before needing the bios refresh).

Will let you know what happens, won't have components to test for a few days.

EDIT: Managed to borrow some 1GB ram to test mobo. No joy. Looks like it's CMOS or thermal paste or bust

Solarjetman on 6/6/2009 at 23:18

Motherboard is dead. Any experience on whether (http://www.newegg.com/Product/Product.aspx?Item=N82E16813131232) P5N-D is a good board? I really don't want to spend more than £50-100.

Recent details of testing:
Cleaning and reapplying thermal paste resulted in a sorry discovery. One of the feet on the CPU heatsink was 'loose', ie. they (the black clip and white foot) fell apart after removing the fan. Nothing was broken, but they did not connect back together well. It was good enough to re-mount the heatsink but it was clearly less stable.

Result of thermal paste was no a win. Mobo still wouldn't go into POST, no bios bleeps, fans and mobo light on as before.

Changing CMOS battery also made no difference.

Thankfully board is still in warranty so is in process of getting a replacement.

Placing all this info together I think the temperature control of the motherboard is whacked out. This would explain the heatsink foot being warped. However, my worry now is that my CPU is also toasted.

If the replacement doesn't work with the current processor them I'm loath to use a new cpu on such an volatile board.

I've been looking into alternatives, so far the (http://www.newegg.com/Product/Product.aspx?Item=N82E16813131232) P5N-D seems a relatively safe alternative... video problem is fixed I think.

I see less and less reason to use SLI. Next rig will be single GPU only.

Solarjetman on 11/6/2009 at 23:42

For those who might be interested... I seem to be going in circles

RMA for motherboard said they could boot to bios and so charged me £20 for the privilage.

Tried my rig set up again, but nothing.

Having managed to secure another CPU I tried it on the returned motherboard. It worked, booted into bios. Went into the bios, changed some memory timings. Then wouldn't post.

Learnt a new trick. You can wipe the CMOS memory by removing chip and rubbing with a magnet. Much more reliable than jumpers. This allowed me to boot again. Went into bios, was changing settings, then everything froze IN THE BIOS MENU. Rebooted but wouldn't post. Did a quick power off and power on, greated with one long bios bleep (motherboard or PSU). Removed power from board and moved the ram. Went into bios, started changing parameters and froze again.

I'm seriously suspecting that board is still messed up, but now I need to verify that PSU is actually working properly. Very depressing. No computer for over 3 weeks now. Gah

Ladron De La Noche on 12/6/2009 at 04:04

You seem to have it covered Solar, keep posting your findings. Not much I can add other than I would suggest to take to a small computer shop and let them handle it for a penny. It would relieve a terrible headache. ;)

bikerdude on 12/6/2009 at 09:34

Quote Posted by Solarjetman

I'm seriously suspecting that board is still messed up, but now I need to verify that PSU is actually working properly. Very depressing. No computer for over 3 weeks now. Gah

You are correct that board is F*****, get it replaced under warranty. But dont let them give you the run around - explain in detail what you have done and firmly state you want a replacement not a repair.