System crash/freeze

[vipigor]

Hello beautiful people. Help

My computer started crashing/freezing about a month ago. I sent it to the repair shop and the guy said (after testing) : We tested all of your components and everything is OK ... so much for diagnostics.

Configuration:

MB Asus Maximus Formula
CPU Q9550
4x1GB Corsair 4-4-4-12 DDR2 800MHz
Extension sound card ( came with the MB)
5870 ATI Sapphire 1gb
2xmonitors
NO OC of any kind


When it started :

One ordinary day (no configuration changes, hardware or software)

Symptoms:
What (Just to make it clear, not always, it can go days with normal use before it happens) :
Computer freezes (sound goes buzzy (loopy)) or sometimes it just restarts on the spot
When :
While playing a game
While playing a game and using flash player (on my other monitor). This case will speed up the time it takes for it to freeze
While watching two full screen flash videos (one on every monitor)
While calculating Windows 7 performance index ( crash on first AERO d3d9 test)



Just to give you and idea on how/when the crashes occur.
Computer freezes
I restart
Try to enter game. At the first instance of engine 3D graphics (not video playbacks or intro) it freezes.
Try to restart and enter the game, freeze.
Try to restart and enter the game, again, freeze.
Try to boot to windows, run mem test, prime, everything ok, no freeze. Try to enter a game/flash video/experience index , freeze.
I shut down the computer and let it be.
Tomorrow:
Come back from work, start up the comp.
Enter the game, it works.
Flash on the other monitor, works. It works for 7 hours and then restart/freeze.
Try to enter the game again, freeze.
Leave it be for 2 days.
Come back, play the game, flash. It works for 5 days .... and suddenly freeze or restart.

My observations, conclusions :
Happens under a lot of activity (but only in previously mentioned conditions ).
No fixed point at witch it freezes / seems random.
Not connected to graphics card directly (What I mean by this is that the card, as a piece of hardware, is not broken)
House power grid is OK (220V +- 5V)
Not connected to any game in specific

What I did to try to fix this:
Measure the input voltage. Passes ok 220V +- 5V
Removed all excess components (sound card, DVD drive, external hard disk).
Removed RAM , replaced it with new
Cleaned everything with high pressure air thingy
Flashed MB bios
Formatted drive, reinstalled windows
Measured temperatures ( all OK, around 50C, full load, just a bit higher)


So it's not the following things :

Sound card
External components
Power grid
RAM
CPU
Graphic card
Heat

Leaves it to:
MB
PSU
GOD ???


What I can do :
1.Bring it back to the repair shop and leave it there till it crashes
2.Buy a new PSU (If somone of you is sure that it is the PSU)
3.Send MB to the repair shop (it still has warranty on)

 

[festerovic]

What kind of PSU are you using?

Is the video card overclocked? That has all the symptoms of card overheating/failing for some reason. Even if it's not overclocked, and is running stock speed, just because the temps are within range doesnt mean the card is cool enough to operate. You may have a card that was not put together as well as another and it needs to be RMAd.

Also, could be drivers. Try older or newer drivers to check to see if things change.

 

[vipigor]

festerovic,
thank you for your brave replay

PSU is some sih**y no name manufacturer (I'm not home now and cant give you an exact answer). The graphic card is brand new , but, the PC was tested with my old card and one Nvidia older card, the problem consisted ... Could it be that the PCI-E slot is somehow failing ? ... i don't know ...


Btw. where are you from ? Possibly eastern Europe ?

 

[festerovic]

I would first look into the PSU, as it's an obvious weak link for phantom menaces like you are dealing with.

"Computer freezes (sound goes buzzy (loopy)) or sometimes it just restarts on the spot " ---I have seen this happen many times when the problem was a driver.

Also, while I can only guess, based off the symptoms, I would blame in order from likeliest to least likely:
1. PSU
2. Drivers, especially sound card.
3. Hard disk failure
4. Motherboard problem like a bent pin on the cpu section.

Sorry these are all guesses, just be methodical and check into the most likely things first and you should find the culprit.

not europe. Heheh, all the "fester"s are taken I had to make a derivative.

 

[vipigor]

Hi festerovic,
Thank you for the guesses I needed for someone to back up my line of thinking.

The only thing left is to try another PSU.

At the moment the comp has 5 days of normal, non interrupted work (without gaming and double full screening). It just has to (thinks in doubt ...) be the PSU ...


I hope that I will shed some light on this situation and come to an answer that will close this thread and potentially help someone through the dark corridors of hardware malfunctions .



I asked because the derivation ended in "ovic" (we have may surnames formed in that way)

 

[vipigor]

Bought my self a new PSU (Corsair TX750). Everything works fine now ... damn PSU-s.

 

[festerovic]

that's great, glad you got it sorted without too much fuss. Also glad you got a good PSU. When you start to add up the time it takes to trouble shoot problems, buying cheap components that you can't trust ends up making the parts cost just as much as getting a quality, more expensive part.