PC randomly shuts down after installing new monitor

[Snellejanus]

Apologies if this is in the wrong subforum, I really didn't know where else it should be.

This week I fatally dropped my crappy old monitor and replaced it with this one.

It works fine, but since then my PC keeps randomly shutting down. And when I say random, I mean really random; yesterday my girlfriend was gaming for 3 hours with no problem (until it eventually did shut down), today I booted the pc and did nothing except open my documents folder which caused it to immediately shut down. I rebooted it and it worked fine, until after an hour or so it happened again while I was just browsing the internet.

It is not overheating; I checked and all my temperatures are fine. Also did a (Avast) virus/malware scan, found nothing. Which would perhaps point towards a PSU problem, also because of another thing that started happening together with the shutdowns: while gaming, my usb controller would keep turning itself off and on. I searched online, and found a suggestion that it could be caused by a lack of power and should therefore be plugged in a back usb port rather than a front one since the ones in the back apparently get more power. I tried and it worked.

All of this is really strange though, since I installed a new PSU less than a year ago. A Corsair CX600. It's 600W, which I'm pretty sure should be more than sufficient for my system.

And anyway, a new monitor should not put any extra strain on the PSU, right? Of course the monitor thing might not have anything to do with it, but it seems very coincidental that both the shutdowns and the controller thing started happening right after I installed it while I have never had those problems before.

Here is some DxDiag info on my system, do let me know if you need anything else:

Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7601)
Processor: AMD Phenom(tm) II X4 850 Processor (4 CPUs), ~3.3GHz
Memory: 8192MB RAM
DirectX Version: DirectX 11
Card name: NVIDIA GeForce GTX 550 Ti
Display Memory: 4049 MB
Current Mode: 1920 x 1080 (32 bit) (60Hz)

Any help would be greatly appreciated! (I'll quickly post this now before my pc crashes again...)

 

[Guest]

The Corsair CX series have low-cost, unreliable components built in, that's the problem. Buy a new Power Supply.

 

[Snellejanus]

The Corsair CX series have low-cost, unreliable components built in, that's the problem. Buy a new Power Supply.

Is there any way for me to test whether the PSU is actually malfunctioning? I would need to be sure before I replace it (and if I want to use the warranty).

And also: if it is the PSU, is it not strange that it would on one occasion shut down with absolutely no demanding tasks running, while on another occasion it can withstand some serious gaming for hours?

 

[Guest]

The PSU you have is unpredictable. It can fail anytime. Try buying a refund - enabled other PSU out, and keep it if it does the job.