Extremely detailed failure - Not sure what is causing it.

[The Mighty Sloth]

First off I would like to post my PC Specs.

CPU:
Processor- AMD FX(tm)-8350 Eight-Core Processor
Speed- 4.0 GHz

RAM:
8.1 GB

OS:
Operating System- Microsoft Windows 7 Home Premium Edition 64 bit

Display:
Resolution- 1920 x 1080

HDD:
500gb WD5001AALS Black

PSU:
750w LSP ATX Ultra Power Supply

Mobo:
Asus m5a99x Evo r2.0 (latest bios)

Tests I have tried

• 
  ●Memtest86+, twice. Each time was over night, no errors.
  ●Prime95, twice. One time for 3 hours, one time for 1 hour. No errors.
  ●Western Digital Data Lifeguard Diagnostic, Ran the extended test, all A Okay. SMART test also passes.
  ●Extensive benchmarking in Metro 2033 (Ultra settings) for 2+ hours. (gpu related, haven't tried furmark yet)

The Issue
My computer crashes, at what I thought was random times. Something to note is that I recently upgraded to a 7990 from a 7950, but had these issues with that card also. I used to think that it crashed at random times, but I have seemed to narrow it down (over 1 year) and think I have a good understanding of it.

Symptomes
Here is a list of things.

• 
  ●Lose all USB inputs that weren't in use at the time of the crash (If I was moving my mouse, I can move it for a bit longer. If I was listening to audio, it loops infinitly.)
  ●For display it does one of two things:
  
  1] Screen goes black, then the GPU fans rev up very fast (Not sure about temps)
  
  2] Imagine if the picture you see on your screen were to duplicate itself on top of it ( towards your ceiling). Now imagine the duplicate being pushed down, and the original going below your monitor (towards your floor). Don't know how else to describe it. Copies itself, then moves down. Only makes one copy or duplicate.
  
  
  ●Audio Loops
  ●Most of the time, about 10 seconds after the crash I will lose all external input.
  ●I know for sure when it crashes because I cannot press caps lock and have the LED light up.

Triggers
●Sometimes it is random. Can happen 5 seconds after windows is loaded (never before), or 5 hours.
●Watching a video fullscreen (Ex: Youtube)
[Wierd] Games don't tend to trigger it (Except CS:GO, I've tried all the "Fixes" ;c || I've tried on metro 2033, arma 3, metro last light)

What I think it is
I personally think it is the PSU. It is ranked very low on the PSU Tier List and is not very much power for my 7990.
Another idea is it could be my motherboard.

Importance of fixing this
Soon I am going somewhere to form a game dev team and I really need my computer to be in working shape.

UPDATE::
Temps are fine, never above 85 on my 7990, and never above ~76-77 on my 8350. I actually underclocked my 7990 to 950 core and 1410 mem.

 

[The Mighty Sloth]

Reserved.

 

[plaintuts]

Try to replace the power supply,

If you're not sure if this will fix then, think about it this way..

A high quality psu is sure to last you atleast 5 years and will definitely not kill other components.
You can still use it on your future builds.

 

[1LiquidPC]

I voted for PSU as well. Even though you had problems with your 7950 as well, the 7990 draws a good bit of power. It should be replaced regardless to be safe. Have you tried a clean install of Windows yet? Temps good? Voltages? Any other peripherals installed around the time this all started? I've had odd driver issues with AMD cards in recent years. Last card I had was a 6990, which I ended up RMA'ing the first one as I thought it was defective. As soon as I'd install the drivers, it would go all crazy with colors, display corruption, and reboot my computer. Safe mode worked fine. Received replacement which was also brand new, same exact thing. Ended up being previous driver remnants. Read a How-to guide on properly uninstalling Catalyst drivers, installed same driver package as before..after that worked fine. Also, maybe the 99% Catalyst bug has returned? If none of these, it may be time to start looking at motherboards.

 

[furkandeger]

I have a similar issue, though some symptoms are not present in my situation. Your system resembles mine in some occasions. I have the same mobo and CPU. I suspect my PSU as well but in my case it is not a no brand one. It's a Corsair CX750M, which is a replacement for my old more "no brand" PSU high power performance 600W. I switched back to my old one and have no issues since. But still It hasn't been long enough to say that fixed it. For details of my situation:

http://www.tomshardware.co.uk/answers/id-2357571/crashes-black-screen-power-cut-restarting.html

 

[The Mighty Sloth]

BUMP For some more help!

 

[furkandeger]

I have a similar issue, though some symptoms are not present in my situation. Your system resembles mine in some occasions. I have the same mobo and CPU. I suspect my PSU as well but in my case it is not a no brand one. It's a Corsair CX750M, which is a replacement for my old more "no brand" PSU high power performance 600W. I switched back to my old one and have no issues since. But still It hasn't been long enough to say that fixed it. For details of my situation:

http://www.tomshardware.co.uk/answers/id-2357571/crashes-black-screen-power-cut-restarting.html

The CX series is not a particularly nice series of PSU.

But as for the main OP, his GPU requires 57Amps on a single 12V rail, and his PSU can only provide 45Amps.

This is one of the reason why AMD is sometimes require High Wattage PSU. Because most cheaper PSU on higher wattage don't actually give you that specified wattage.

For example, A PSU advertise as 1000W can only provide say 800-900W or a PSU as 750W and only can produce 600W or something like that.

But compared with branded PSUs, whats shown is normally what you will get i.e. an XFX 750 Watts from Core series actually can produce 750Watts power.

For the Op though,

You can check the PSU list found here: http://www.tomshardware.co.uk/forum/id-1804779/power-supply-unit-tier-list.html

I recommened the Tier 2 Class A > Good Quality and good prices.

Personally I recommend the

XFX Core and Pro Series, they are good quality PSU and have lower price nowadays
EVGA B2 is also good they are advertised as Bronze but actually they are right at the edge of being a Silver rating PSU which is really really good.

Actually here it says 48A for 7990. Even though OP's PSU still cannot give that, it's not as high as 57A.

https://forum-en.msi.com/faq/article/power-requirements-for-graphics-cards

 

[The Mighty Sloth]

I have a similar issue, though some symptoms are not present in my situation. Your system resembles mine in some occasions. I have the same mobo and CPU. I suspect my PSU as well but in my case it is not a no brand one. It's a Corsair CX750M, which is a replacement for my old more "no brand" PSU high power performance 600W. I switched back to my old one and have no issues since. But still It hasn't been long enough to say that fixed it. For details of my situation:

http://www.tomshardware.co.uk/answers/id-2357571/crashes-black-screen-power-cut-restarting.html

The CX series is not a particularly nice series of PSU.

But as for the main OP, his GPU requires 57Amps on a single 12V rail, and his PSU can only provide 45Amps.

This is one of the reason why AMD is sometimes require High Wattage PSU. Because most cheaper PSU on higher wattage don't actually give you that specified wattage.

For example, A PSU advertise as 1000W can only provide say 800-900W or a PSU as 750W and only can produce 600W or something like that.

But compared with branded PSUs, whats shown is normally what you will get i.e. an XFX 750 Watts from Core series actually can produce 750Watts power.

For the Op though,

You can check the PSU list found here: http://www.tomshardware.co.uk/forum/id-1804779/power-supply-unit-tier-list.html

I recommened the Tier 2 Class A > Good Quality and good prices.

Personally I recommend the

XFX Core and Pro Series, they are good quality PSU and have lower price nowadays
EVGA B2 is also good they are advertised as Bronze but actually they are right at the edge of being a Silver rating PSU which is really really good.

So would something like this suffice?
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

 

[The Mighty Sloth]

can you put a new link, that link you placed it sends me to front page of newegg :/ just put maybe the name of the PSU

by the way you have 8.1GB of Ram?

Just wondering, what is your ram's name/Brand/MPN and are you using dual channel or quad?

http://www.newegg.com/Product/Product.aspx?Item=N82E16817207011

If that still doesnt work, then type this in google.
XFX Core Edition PRO850W (P1-850S-NLB9) 850W ATX12V / EPS12V SLI CrossFire 80 PLUS BRONZE Certified Active PFC Power Supply

I accidentally typed 8.1 lol. They are GSkill Ripjaw (Look like these : http://www.newegg.com/Product/Product.aspx?Item=N82E16820231428 )