System freezes during memtest with a specific graphics card??

[Moeboid]

System:
CPU: i5 750
GPU: Gigabyte GTX 460 1GB overclocked (factory)
PSU: Corsair HX 650
RAM: Corsair CMX4GX3M2A1600C7 2x2GB
HDD: Samsung Spinpoint F3 500GB HD502HJ
Motherboard: Gigabyte GA-P55A-UD4 rev 1.0

When I try to run memtest on this system, it fails. It never returns an error and sometimes it can last a few passes, but eventually it just stops testing. Strangely, the cursor (I think that's the right word...) and the "+" continue to flash as normal on the screen so I guess part of the system is still working, but the test stops and it won't respond to the keyboard. When I replace the graphics card with my old MSI 8400GS, it runs with no problems. The graphics card works perfectly in at least 3 other systems, and using a more powerful power supply makes no difference. What on earth could be going on here?

[perrymitchell]

Does it freeze during normal operation? Try running some stress-tests inside windows. If it doesn't bail, I'd just forget about the memtest.

[OldnBold]

Hard to tell if we don't know if you are running the ram at it's rated speed.

Are you overclocking the ram? Do you have it running at rated SPD in bios?

[Moeboid]

I've run some more tests and at the moment it looks like my graphics card is faulty. I managed to get it to fault in a friend's system. I can't explain why I couldn't get it to fault on other systems. I'll have to run some more tests tomorrow.

Yes, it freezes during normal operation. The strange thing is that it doesn't necessarily freeze while it's doing something stressful. Sometimes I can play demanding games for hours on end with no issues. Other times (most of the time) it'll fault before it even loads windows. Very strange issue.

[Boooooo]

@Moeboid
I registered here for contacting you (look private message) and searching for a solution.
Is incredible I have the same issue with a complete different hardware and even I noticed that swapping video card makes memtest86+ run ok.
We only have very similar DDR3 memory, have you tried a different one?

Brief summary:
My system suffers of completely random freezes (fortunately not so frequent, can occurs once in 5-6 days or even twice freezes in a row in the same day).
Freezes can occurs in idle as while playing game/watching video/surfing internet I want to say a stress test (CPU or GPU) doesn't guarantee the freeze.

First I thought was Windows 7/driver/software issue, then I realized the problem is absolutely hardware related (and not related to overheat), how can I say? Accidentally I find out freezes can occurs (in the first 3 minutes or even after 5 hours) even simply resting in bios setting page! Or similarly, doing a memtest86+, that means no driver/software are still loaded.
NEVER had a BSOD or one memtest86+ error!.

So "resting in bios" or "doing a memtest86+" (in both test CPU and GPU are not controlled by Cool&Quiet or PowerPlay so are a sort of "mild" stress tests) define "conditions of freeze" useful to "test and verify" if freeze problem persists after making some hardware modifications.
So thinking of a memory issue I started working with DDR3 voltages/timings/frequency even working a bit with motherboard voltages (northbridge, CPU etc.) but with no result-->making the previous tests overnight make system freeze nearly 100%

One day I swapped my VGA with another one, (my motherboard has not an integrated one, the one I plugged doesn't need power supply) and incredibly memtest86+ pass the overnight test; fortuity? It passes a second night of 16 hours of test. So I could say the problem is restricted not more with memory but with: my original VGA or power supply. Let's restrict further

My PSU provide 2 PCIe power connectors so I tried swapping but with no result. Then I stopped using the PCIe connectors and used the "molex to PCIe" converter connector that is provided with the VGA; first attempt failed, then second attempt, draining power from another molex was sucessful! Fortuity? It passes a second night of tests. So me and you can say "finally you find there's a problem with PSU", unfortunately no infact...

Remaining with this "molex to PCIe" that means the configuration doesn't make memtest86+ freeze (unless it freezes after 16 hours or more) yesterday I had 2 freezes in the same day while I was surfing in internet
I noticed that after rebooting after a freeze HDMI audio is disabled and I have to unplug and plug the cable again to my monitor, can this be an hint that's a VGA related problem?

So all my researches are at the beginning again, in these days I can have a chance to swap DDR3 memory

My hardware is quite new and all updated, even motherboard and VGA bios. I don't have a tester for the PSU but bios voltages/temperatures/fan speed page show me max 42°C for CPU and all voltages (+3V,+5V,+12V) are above the correspondent value.
Tonight I rested in the bios voltages/temperatures/fan speed page to see if freeze occurs for a drop in voltages values; freeze occurred but all the values shown by the frozen screen were correct
Sorry for my English

[Boooooo]

sorry I forgot my specifications

[Moeboid]

Hi Boooooo,

unfortunately, I still have no idea what's going on. Like I said before, it looks like my graphics card is faulty, but the strange thing about that is that this graphics card is actually a replacement for my first graphics card, which was also faulty... I'll be getting a replacement card soon, so I'll let you know how that goes. I must say though, I'm not feeling very optimistic.

[Boooooo]

Hi some questions:
Have you got integrated VGA card?
Your "faulty" VGA need power supply? If yes can you try using a molex to PCIe converter? If freeze occur the same during memtest86+ change the molex
Have you tried changing DDR3 with a different one?

Make this test for me please: rest overnight in bios setting page (better if in the page where is time informations so that you can see when freeze occurred)


edit: have you tried update motherboard bios?