random PC shutdowns, new build, cpu and mobo RMA tested and all ok.

DBT85 · 8 Oct 2010 at 15:52

I built a pc for a family member a month or so ago and while fine for a week or so it started shutting down at random times. It will sit at idle in Windows fine for hours on end but as soon as you start doing anything it will start restarting. Sometimes it'll be 5 minutes into an OCCT test or a virus scan or even word, other times it'll be 40 minutes or even 2 hours.

Not having any socket 1156 parts spare i couldn't test the motherboard or CPU so after swapping out other components (except the ram) and after running memtest for 16 hours and finding no problem i concluded that it must be either the cpu or the motherboard. Those have just been dispatched from OCUK after running prime95 for 16 hours with no problems.

So, since i tried a fresh Windows XP 64 install with all updates and all drivers installed what are my other options?

The only thing I can think is that despite memtest not saying anything it has to be the ram. I've tried my corsair PSU which is perfect for my more powerful rig and it made no difference, i tried my Giga 460 GTX in place of the onboard video and it made no difference.

The only things I've not tried doing are running with any other ram and with a different HDD. But as I said, memtest said the ram was fine and I cant see the HDD causing it to reboot.

It definitely wasn't overheating as I checked continually.

Here is the build:

Intel Core i5 650 3.20GHz
Patriot Viper 4GB (2x2GB) PC3-10666 1333MHz
Gigabyte GA-H55M-S2H
Seagate Barracuda 7200.12 500GB SATA-II 16MB
Xigmatek Asgard Midi Tower Case
OcUK Swift 450W Silent Power Supply
LG GH22NS50 22x DVD±RW SATA ReWriter

Thoughts?

anuraj · 8 Oct 2010 at 15:57

Power supply seems a bit bad so I'm going to go with power supply is not a good one.

DBT85 · 8 Oct 2010 at 16:04

anuraj said:
Power supply seems a bit bad so I'm going to go with power supply is not a good one.

as i said in the OP, tested with my corsair which is fine in my much more powerful rig with no change...

edscdk · 8 Oct 2010 at 16:05

jsut because the system runs prime for hours does not mean the mobo is not faulty...

I had two recently that ran prime for hours but would after closing prime then crash / reboot afer a number of hours doing nothing or jsut opening word)

if friends / family ever want a PC i get them a pre-built machine... its a lot less trouble for you...

try 1 stick of ram if you ahve not already

edscdk · 8 Oct 2010 at 16:13

long shot but if oyu rule out all else try it outside the case, maybe there is some weired short..

Ryan-3 · 8 Oct 2010 at 16:30

+1 to trying it outside, on a test bench style, see if shorting is the problem.

DBT85 · 8 Oct 2010 at 16:32

edscdk said:
jsut because the system runs prime for hours does not mean the mobo is not faulty...

No but the fact that when I do it with all the components it crashes and when OCUK do it with only the mobo and chip it doesn't do it kind of points in that direction.

edscdk said:
if friends / family ever want a PC i get them a pre-built machine... its a lot less trouble for you...

I'll not be doing this again. Its cost me £22 to send these bits back to have them declared ok and I know when I try and ask for that money its going to get political.

edscdk said:
try 1 stick of ram if you ahve not already

already tried that, then tried with the other stick. no joy.

Wondering if the ram just needs a little more juice. It was set in the bios to what the lable said it needs though.

thanks for the help though.

Anewbe4u · 8 Oct 2010 at 17:02

What are the temps like when it crashes?

Hagar · 8 Oct 2010 at 17:03

Todge said:
Wondering if the ram just needs a little more juice. It was set in the bios to what the lable said it needs though.

thanks for the help though.

What have you set it to?

try 1.65V if it is set below that.

andy.

Boo_hoo · 8 Oct 2010 at 17:09

Try a different PSU with your mobo. I know you said you tested it but it could be a combination

Also could be software/os related. Download and try Ubuntu, you don't have to install it.

Could be a faulty wire. Sadly there is no one constant answer. Just gonna have to go through a process of elimination.

DBT85 · 8 Oct 2010 at 18:39

Anewbe4u said:
What are the temps like when it crashes?

normal operating temps, i cant recall off hand but even under full OCCT it wasnt going past 60.

nkata said:
What have you set it to?

try 1.65V if it is set below that.

andy.

will give it a whirl ta.

Boo_hoo said:
Try a different PSU with your mobo. I know you said you tested it but it could be a combination

Also could be software/os related. Download and try Ubuntu, you don't have to install it.

Could be a faulty wire. Sadly there is no one constant answer. Just gonna have to go through a process of elimination.

I'm going to run it on the dining room table out of the case and see what occurs. That'll have to wait until monday though.

DBT85 · 13 Oct 2010 at 16:24

We'll after the DPD guy managed to knock on my door and leave a card while I was home on Monday (There was no nock and no card...) it was redelivered today. My brother lent me a 2gb ddr3 stick to test out and it stayed stable for well over an hour with his ram in. With the original stuff it died within 15 minutes of OCCT.

Knowing that it was therefore the ram i did as nkata said and raised the ram voltage from 1.5 to 1.64 and sure enough its now 2 hours into OCCT crash free.

The label on the ram clearly states 1.5v but apparently it is a filthy liar. Finally its all over. Never building a PC for family again.

shadow_boxer · 13 Oct 2010 at 19:14

Glad to hear you've got it sorted mate. Did you buy the ram from ocuk?