Computer Problems, need some help

[TheAmmoniacal]

Other forums dedicated to computer hardware have been less than helpful, so I'll give this place a try.

My computer is having (apparently) random and very intermittent freezes/crashes

Sometimes it freezes with a buzzing noise like this: https://youtu.be/KmJFVgOg34E?t=1s -- other times is freezes without any noise. This happens 2-3 times a week, and appears to be unrelated to anything I am doing. It doesn't happen any more frequently if I stress test my hardware, but it does appear to happen less frequently when I'm running Ubuntu (once a week). I'm currently on Windows 10 Insider Preview (the issues is not related to any particular build of Windows 10, been more or less the same on all).

I'm completely lost here, where do I start diagnosing this? Help/advice are very much appreciated, I'll run whatever tests seems reasonable.

The PC I had previously had major EMI issues, it would freeze up similarly (but without noise, ever) every time I put my mobile phone close to the motherboard (ASUS Maximus VII Impact), or if the phone was ~1 meter away from the PC during a call. Could it be something this obscure, again?

Hardware

• CPU: Intel Xeon E5-2690v3
• GPU: EVGA 970 GTX SC 2.0
• SSD: Samsung 950 Pro, M.2, NVMe, PCIe
• RAM: Crucial 32GB Kit (4 x 8GB) DDR4-2133 RDIMM (CT4K8G4RFS4213)
• MOBO: AsRock X99 WS (gone through several BIOS versions, no change)
• PSU: EVGA SuperNOVA 1000W G2

[PA0PBZ]

Where is the sound coming from?
(And why is the program in Dutch?  )

[TheAmmoniacal]

Where is the sound coming from?
(And why is the program in Dutch?  )

That's just a random video I took off youtube, not mine! The sound is coming from the speakers (headphones), i.e. out of the on board audio card.

[SeanB]

First, have you taken it apart and checked all connectors for power and data, and applied any firmware updates? If so run Memtest and leave it to run for at least a day so there are no RAM issues, and then if no issues try turning down processor speed and memory timing to a more conservative setting,  and check the power rails for ripple.

[PA0PBZ]

Make sure that the system is not overheating, so take it apart and remove the dust form the CPU and GPU heat sink.
Also get the latest driver for the GPU.

[continuo]

Your GFX card seems to be some factory overclocked GTX 970. Try to set its clock rate to nVidia default level, there have been many reports of such overclocked cards got unstable after some amount of time.

[TheAmmoniacal]

Fist, have you taken it apart and checked all connectors for power and data, and applied any firmware updates? If so run Memtest and leave it to run for at least a day so there are no RAM issues, and then if no issues try turning down processor speed and memory timing to a more conservative setting,  and check the power rails for ripple.

I have taken the PC apart a few times for cleaning/sorting and installing new hardware, still hasn't made any difference to this issue. Only installed firmware updates for my SSD, afaik. The GPU and CPU both operate well within safe temperature range, the CPU don't pass 60 C on any single core even on full load (Noctua NH-D9L). The GPU to hover around 70 C when loaded.

I will run memtest overnight.

[German_EE]

Please check the 12 volt, 5 volt and 3.3volt power supply lines and make sure that the voltage is as close as possible to the correct amount. If they look OK then leave the meter on one of the lines and see if it alters during a crash.

If you have one an oscilloscope is a much better way to check the power supply lines as you can check for noise.

[nctnico]

Is it connected to a properly grounded outlet? Any ESD discharge sources?

[Halcyon]

The sound is coming from the speakers (headphones), i.e. out of the on board audio card.

My machine at work does exactly the same thing, although it's an Acer and an absolute bucket of crap so I expect no less.

I think your motherboard might just be cheap and nasty. I'm generally not a huge fan of "consumer" motherboards, the closest I'd recommend would be Intel. Your previous ASUS board is a prime example of something that isn't designed properly. The last time I came across a machine that couldn't handle EMI was an old laptop which would lock up every time you hit the PTT talk button on an AM CB radio.

[nogood]

The buzzing sound just tells you that basically everything software just crashed. IIRC this sound ist just the soundcard reading the same samples over and over again, because there is no sound driver to load anything else in there...
I had this, when my PSU would fold back the voltage to save itself, then of course immediately returning it, thus leading to me having a frozen picture and buzzing.

[Stonent]

My thoughts are overheating of something.

[ade]

I'd also suspect improper grounding.  The buzzing sound is likely from the 50 Hz mains cycle. 

Check the outlets, PSU, chassis for proper grounding and that no cables / mobo connections are getting shorted.

[amspire]

When I have had computers freezing, the most likely culprit is usually the power supply. I know the one you have a good quality and powerful one, but it is the first thing I would try and swap out. In one case, I had 8 PCs I was building with a reasonable quality ($100) 600W PSU. These only had a mid-range graphics card and no overclocking. Every PC was freezing randomly. I was able to swap the PSUs for a different 550W model from the same manufacturer and the freezes were gone. Sometimes for some unknown reason, a certain model power supply doesn't work well with a certain model motherboard. There will always be a technical reason, but I have never taken the time to debug it.

If you can get your hands on a 600W or higher PSU, even if it is a much lower quality one then the current PSU, try it. With power supplies, if it is a good brand name, then you can expect it will supply the rated power. Without looking up the specs, I would expect your system is still under 600W. This is not necessarily a permanent fix - this is to see if your PSU is the problem.

A second common problem is the RAM. Some motherboards just do not handle a full complement of large RAM well. I have two identical motherboards here at home - one can handle four slots easily, and the other can only handle two slots of large RAM reliably - freezes with all 4 slots loaded. That is an easy one to test - just reduce ram to 16G. If it still freezes, take out the 16G and put the other 16G in.

If the CPU has not had the thermal compound applied well, it can be worth removing the heatsink, cleaning the old compound off, adding a small amount of new compound. I have come across PCs that were assembled without any thermal compound, but if the temperatures are OK, this is not my first guess.

It can always be the graphics card, and the only thing you can do there is to plug in another card (even if it is a cheap $30 one) and see if the freezing stops. It is not a very conclusive test, but if the freezing still happens with a low powered GPU, then at least you know the problem is not the GPU and is not a power supply high load problem.

The noise is rectified mains noise getting though to the motherboard. It is the sound of 100/120Hz plus lots of harmonics. It can be an earthing problem as suggested, or a fault in the PSU.

Disconnect any external USB devices, such as printers, that have their own power supply. Powered speakers. Ethernet connections wouldn't be the problem. The monitor could be - try replacing it temporarily.

[AntiProtonBoy]

You might also want to get the latest chipset drivers from the motherboard manufacturer.

[Brumby]

I'd also suspect improper grounding.  The buzzing sound is likely from the 50 Hz mains cycle. 

I don't believe that would be the case.  If it were, the OP would be complaining about the buzzing being there ALL the time.

[ade]

I don't believe that would be the case.  If it were, the OP would be complaining about the buzzing being there ALL the time.

Not necessarily the case.  The obvious one is if the grounding issue is due to a intermittent connection.

A more common symptom is if the computer sometimes freezes or make noises when there's a second path to ground.   E.g., when the case is touched, when devices are being plugged in (e.g., USB, has a GND connection), etc.

That the mobile phone caused previous problems with freezing is also suggestive of poor grounding.

OP: does the computer freeze when you're actively working on something, or only when it's idle for a bit?

[TheAmmoniacal]

It has only happened once that the PC froze up while I was not using it (waking up one morning finding it unresponsive).

memtest86+ passed, no errors.

Can't find much useful information on downclocking the GPU, ought I not also lower the voltage? To what?

I wouldn't know how to trace down grounding problems. But I could provide another potential key to the puzzle, if the metal shroud of my HDMI connector (hooked up to the monitor) touches my PC chassis that can cause it to freeze up instantly.

[amspire]

I wouldn't know how to trace down grounding problems. But I could provide another potential key to the puzzle, if the metal shroud of my HDMI connector (hooked up to the monitor) touches my PC chassis that can cause it to freeze up instantly.

That sounds really bad. Have you checked if both PC case and the monitor are connected to earth at all? You could be talking about something as simple as a power cable with a broken wire or a bad power socket wiring.

Have you checked the potential between the PC chassis and the shroud on the HDMI with a multimeter on both DC and AC volts?

[nogood]

I dont think the buzzing comes from the mains, but maybe you can upload a sample if the computer crashes in the near future. that sounds exactly like a stuck soundcard buffer.
About freezing up when touching the chassis with connectors:
I do also have that problem, everything is earthed as far as that goes. My suspicions are that the chassis is connected to mains earth through the PSU and the connectors are not (directly, but have some mains earth referenced leakage on top ?). I can throw tiny sparks when I touch the chassis while pluging in powered USB-Devices, then my PSU goes haywire because it thinks something is wrong.
This then leads to a OS Crash/Freeze and buzzing through the unfed sample buffer of my soundcard.

But if your computer freezes in the same manner withoug plugging something in etc., then i would suspect some fault with your PSU (first guess).
If you can loan an old PSU from somebody, you can test this (maybe not the plugging in issue), and then go on to suspect other parts.

In my experience PSUs after faulty RAM are often the cause of intermittent faults.

PS: Is your monitor by any chance hooked up through a double isolated (no earth) PSU ?

[nctnico]

The sparks from the USB devices are probably caused by switching PSU wall-warts

[nogood]

The sparks from the USB devices are probably caused by switching PSU wall-warts

Yes I think so too. I have read in some "sources" that it is a problem of "static electricity", but I think it is just leakage from those PSUs.
Seeing how LED-backlight monitors are now coming with external non earthed supplies, that may very well be the cause of the sparks from the HDMI connector.

[FreddyVictor]

how old is the motherboard ?
my last 2 pc's have died due to failed capacitors on the motherboard, but I have to say, they were older ones and most manufacturers are using better ones nowadays...

[continuo]

Can't find much useful information on downclocking the GPU, ought I not also lower the voltage? To what?

Download the "EVGA Precision X" Tool from their website, this should be the right tool to downclock the card. Rising the core voltage a tad may also be worth a try   

[Psi]

The sound in that video is just the soundcard buffer looping whatever it has in memory after the whole system crashes.

I suspect you are getting rather large spikes coming in on the mains and its crashing the PC. Try a Spike protector on the PC power plug.

But other things to check as well are
- Run Memtest all night long to look for memory errors
- If running dual channel ram try a single stick.
- Remove all PCI/PCIe cards and see if the problem goes away
- Check SMART diagnostics for your hard drive for problems
- Is this PC overclocked? If bought second hand it may have come that way. Maybe do a bios reset to defaults. (Note that windows may not boot with defaults settings if it was installed with non default settings, so you may need to reinstall with defaults set.)
- Check CPU temp
- Check Motherboard for bulging capacitors
- If you are experienced and ok with opening up 110/230v devices then open up and check the powersupply for bad caps