(Computer Issue) Random horrific lockups.

[Nephtys]

So I built a computer about a year and a half ago, and it's been great. Except for one issue. Sometimes, during intense activity (Particularly 3D games and video conversion), the whole system locks up. The sound goes into that horrible lock-up (HRRRKGHGHHH) mode, and sometimes the screen glitches out into rows of scattered chaos, or sometimes it just holds the image.

I'm not sure exactly what could be causing this. Since it can be a number of factors. Sometimes it doesn't happen for a month, and sometimes (like today!) it happens twice in a row while I'm playing a game online, causing no end to frustration.

My Video Card?
My RAM?
My Motherboard?
The CPU?
Powersource?

Not sure really, since any of these could be it.

Intel Quad Q9400 (2.66GHZ) Core
8GB DDR2 RAM
550W Corsair Power Supply
nVidia GeForce 9800GT
Gigabyte GA-EP45-UD3P Motherboard

Any suggestions on the possible causes and ways to diagnose?

I don't think it's the video card. I've swapped it between my PCI-E slots and even exchanged the unit. It's also staying within temperature constraints. I don't think it's heat entirely either, as sometimes it used to happen within minutes of a reasonably cold startup (as in, computer off for more than an hour).

[White Haven]

Have you tried testing with one half of your RAM in, then the other half if it fails? That should nail down if you have a failure in a stick of RAM quicker than testing each stick alone given the intermittent nature of the problem. I don't really trust diagnostic software on a problem this intermittent, too easy to get a false positive on bad hardware.

[General Zod]

If it was happening during casual use and intense activity I'd probably wager on the RAM, but if it's just happening during intensive 3d stuff then it sounds video-card related. Swapping out with components that are known to be good is the only way I can think of to test it if it's consistently happening only during certain activities.

[Civil War Man]

Out of curiosity, what OS are you running? If you are running 32 bit, half of that RAM isn't doing you any good, anyway.

[Nephtys]

Out of curiosity, what OS are you running? If you are running 32 bit, half of that RAM isn't doing you any good, anyway.

Vista 64. I kept that in mind.

Not sure really about how to test it even with the RAM. The crashes are so erratic, it's impossible for me to predict when they'll happen. Since I could play a game for 3 hours, or for 10 minutes and it could crash at any time... or not at all.

[Genii Lodus]

I have similar crashes. My CPU and GPU were both running hot so I reseated the heatsink on the CPU and replaced the one on the GPU with a custom cooler. The overheating problem is solved but I still get crashes in some games. I can leave the system running Prime95 and FurMark for over an hour with a crash with the CPU and GPU both maxed out. The two games that crash most frequently are GTA IV and Borderlands, the latter is curious as I've run many other UE3 games without issue.

You can try testing your RAM by using the inbuilt memory diagnostic tool Windows Vista and upwards come with. A search for memory diagnostic in the start menu should bring it up or you can run it from the start-up menu (F8) before Windows boots.

[General Zod]

I have similar crashes. My CPU and GPU were both running hot so I reseated the heatsink on the CPU and replaced the one on the GPU with a custom cooler. The overheating problem is solved but I still get crashes in some games. I can leave the system running Prime95 and FurMark for over an hour with a crash with the CPU and GPU both maxed out. The two games that crash most frequently are GTA IV and Borderlands, the latter is curious as I've run many other UE3 games without issue.

You can try testing your RAM by using the inbuilt memory diagnostic tool Windows Vista and upwards come with. A search for memory diagnostic in the start menu should bring it up or you can run it from the start-up menu (F8) before Windows boots.

I'm convinced GTA4 was coded by a bunch of half retarded howler monkeys. It clogs up resources needlessly for what seems like minimal details. Borderlands could be a shader issue or something thanks to the art style.

[Genii Lodus]

Yeah I have an 8800GT which is near enough the same chip as your card so it might be some kind of driver issue. My comp hasn't crashed in anything apart from those two so I'm inclined to think that most of the other crashes were down to the overheating while those games are something else.

I'll be getting a new GPU in a few months, barring any unforeseen emergency outlays, inclined to go to ATi because their cards tend to be cooler and less power-hungry than the equivalent nVidia card. If that replacement still doesn't solve the issue I'm out of ideas as to what it could be.

[Dominus Atheos]

Don't assume it's a hardware issue. If Windows has been running on that machine for the past year and a half, it could easily be that it's accumulated too much cruft and that's what's causing the problems.

Try doing a system restore to before you had the problem. That would also fix any driver issues.

[Nephtys]

Don't assume it's a hardware issue. If Windows has been running on that machine for the past year and a half, it could easily be that it's accumulated too much cruft and that's what's causing the problems.

Try doing a system restore to before you had the problem. That would also fix any driver issues.

I've considered driver causes, and the computer has done this sporadically ever since I built it. I've also updated my video drivers and it still does it. Likewise, I don't think this explains how the machine freezes during other applications, such as video conversion.

[Ace Pace]

Run Memtest, see if it brings up problems with the RAM. The problems you describe can possibly be attributed to that.

[phongn]

Run Memtest, see if it brings up problems with the RAM. The problems you describe can possibly be attributed to that.

There's also IntelBurnTest for stressing all non-GPU aspects of a computer.

[Nephtys]

Had another crash earlier today while playing League of Legends.

The windows Memory Tester didn't seem to pick up anything off. I'm going to try IntelBurnTest now.

[Enigma]

Have you tried checking your hard drive?

My in-laws had the same problem and it turned out that the video card was toast.

After installing the new card the crashing still happened but it took a lot longer for it to happen as opposed to before it would crash within a couple of minutes after loading WinXP. But that problem was fixed just by running Spybot, AVG and some other software I forgot the name for. Plus I cleaned out the chassis.

[Nephtys]

I'm stable at the max mode of Intel Burn Test. Core Temp is remaining well within safe limits during this.

Not sure how I can 'check' my HD without swapping out for another one and loading the OS on it.

This video card is unlikely to be the problem, since I had already swapped it out from the old one during the early days of this machine. After both, it still had the same occasional behavior.

[Starglider]

You could try plugging your hard drive into a different SATA port, thought that isn't likely to make a difference. I suspect the motherboard northbridge is faulty.

[Civil War Man]

If you want to check your hard drive, you could burn a copy of Hiren's Boot CD. It contains diagnostics tools for all the big name brands.

[noncredible]

If it only happens to online games, maybe the game tries to send more information at a time than your computer can handle. When playing online games and it freezes, have you tried unplugging the internet and waiting a while?

[Nephtys]

If it only happens to online games, maybe the game tries to send more information at a time than your computer can handle. When playing online games and it freezes, have you tried unplugging the internet and waiting a while?

It's virtually any game, and some applications like video conversion. Sometimes it happens within 10 minutes, sometimes it doesnt' happen even if the computer is converting overnight.

Plus, that wouldn't literally lock up the system.

I fear it may be the Mobo/CPU itself.

[Enigma]

Does it lock up even if you are doing nothing?

[Nephtys]

Does it lock up even if you are doing nothing?

More or less no. I think it may have done so once or twice, but that's likely because I had something in the background. Usually it takes a game, or video conversion, or (rarely) watching a video.

[Starglider]

If it only happens to online games, maybe the game tries to send more information at a time than your computer can handle.

That makes absolutely no sense. Aside from the fact that overflowing the TCP buffer wouldn't cause a lock-up, no home PC is ever going to have a problem handling the bandwidth you can get on a home internet connection, even 100 megabit fibre.

[Luke Starkiller]

Have you looked in Event Viewer for any warnings or errors that are being logged at the time it locks up? That might give you a more specific direction to look in.

[Dominus Atheos]

Okay, let someone who has done professional tech support for 3 1/2 years help you instead of a bunch of random people on a web forum dedicated to arguing about whether the Enterprise could beat up a Star Destroyer.

Troubleshooting is a five step process. Step one is "Identify the problem":

Your computer may lock up whenever it's resources are taxed.

2. Gather more information:

How long have you been having this problem?
Has it gotten worse recently?
When it locks up, does the light on the keyboard come on when you press the Caps Lock button? (I know this question seems random, but trust me it's important)
So you tested or replaced the memory, CPU, and Video card and they came up fine; is that correct?
You are running Windows Vista x64, correct?
This happens during 3d gaming and video conversion, correct? Is there any other action that has caused this issue, or are those the only two?

3. List possible causes (Pending your responses to the above):

OS issue
HDD issue
Motherboard issue

4. Isolate the fault (In order of how difficult and expensive it would be to do so):

A. Download and run Seatools for Windows including the short self-test and long self-test. If either of them fail then replace the HDD. If it locks-up during either of the test than restart the computer and try running it again until it completes. If it always locks-up at the exact same point during the test then replace the HDD. If it locks up during random points then continue to the next step. If it passes then continue to the next step.
B. Insert a Linux live cd and see if you can recreate the issue with that. If you can't then backup your data and reinstall Windows from scratch. If you can recreate the issue with a live cd then continue to the next step.
C. Replace the motherboard.

5. Verify functionality

Try playing a 3d game and converting videos to make sure everything works correctly. It it doesn't then go back to step 1.

[Zaune]

This sounds a hell of a lot like a problem with my PC that I eventually traced to a bad power supply, though in that case the lock-ups were almost entirely random. Unfortunately, you really need proper testing equipment to rule that out.