Computer shuts down under load, new PSU, Intel i5, temps normal

[Ryan Young]

This one has me baffled, I need some other thoughts on the subject.

Setup:
i5-3550, Stock Cooler
New 450W PSU
MSI B75MA-E33 Motherboard Amazon Link
4G Ram

This is my HTPC. I've removed the AMD HD6450 video card since the i5 i put in can run HD video with no problems.

However, when I push the CPU past 50C or 50W the computer shuts off completely, no BSOD, then restarts. There is no Windows message telling me there was a failure either.

I've tried everything, including watching the temps as I turn on Prime95 and an HD video from YouTube, but there is nothing that points to a problem. I disabled all but one core and the computer stays on for slightly longer, which to me says it is a power issue, but 50C should not be enough to shut down the sytem, and the BIOS says 70W is the short-limit for a power spike.

What am I missing here? The problem has become more frequent lately and it is driving me crazy!

 

[Catalyzer]

Which Brand PSU you have there ?

 

[i7Baby]

Can you check voltage for the CPU? It might be a PSU problem. 50C should be OK.

 

[Ryan Young]

The PSU is an "XOK" Korean brand (I live in Korea right now). The problems were the same for the last PSU, which I don't think I needed to replace now.

 

[Catalyzer]

The PSU is an "XOK" Korean brand (I live in Korea right now). The problems were the same for the last PSU, which I don't think I needed to replace now.

Take a good PSU , thats all !
That PSU cant handle loads at all it seems.
even 430W corsair PSU is enough for your build (Minus the gfx card)

 

[i7Baby]

Its important to have a good quality PSU. You're lucky your mobo or CPU wasn't permanently damaged. You can double check by looking at voltage ouputs. If the 12V rail isn't 12.0+/-0.2 V or the 5V rail or 3.3V rail accurate then you can have big expensive problems.

 

[Ryan Young]

Thanks for the feedback guys. I'm going to test the voltages tomorrow and probably try moving my Corsair 1000W PSU in my main rig into the problem one to see it the issue remains. I have a hard time believing two PSUs would have the exact same issues. Is the CPU power a common problem area?

 

[Baralis]

Thanks for the feedback guys. I'm going to test the voltages tomorrow and probably try moving my Corsair 1000W PSU in my main rig into the problem one to see it the issue remains. I have a hard time believing two PSUs would have the exact same issues. Is the CPU power a common problem area?

I am not familiar with the "XOK" brand or your particular model but many lower quality PSUs cannot maintain their advertised wattage, instead their advertised wattages are essentially peak and temporary limits and they cannot reliably handle a sustained load anywhere close to that.

 

[gamerk316]

Yeah, there's a LOT of PSU brands out there that can't sustain anywhere near their advertised wattage. That's why most of us stick to proven brands and older, proven reliable, PSU's.

 

[Ryan Young]

That all definitely makes sense. However, it is just hard to believe that an advertised 450W PSU can't push one SSD, two fans, and my CPU at 50W. I'll report back when I troubleshoot some more.

 

[Ryan Young]

Ok, did a few more troubleshooting steps:

1) Plugged a USB drive in with a Ubuntu distron on it. Ran Prime95, died like the Windows 7 SSD drive.
2) Opened up my big tower, ran the CPU off the 1000W Corsair, died like the rest.

What is the next step? It is either the motherboard now, or the CPU. I'm thinking it is most likely the motherboard. I guess I'll try putting the i5 into my big tower and see what happens.

Thoughts?

 

[Ryan Young]

Photo of my headache...

 

[Baralis]

I would look to your motherboard being the culprit next. CPUs are probably the most reliable part of a PC and rarely are the cause of issues in comparison to all other components.

I would give your motherboard a close visual inspection to check for bulging capacitors or burn marks. If you are able to return the motherboard for a replacement I would try that option next.

 

[i7Baby]

I'd say you're on the right track. I think the PSU has caused damage - probably just to the motherboard. But you need to try the i5 to verify this.

 

[Ryan Young]

I would look to your motherboard being the culprit next. CPUs are probably the most reliable part of a PC and rarely are the cause of issues in comparison to all other components.

I would give your motherboard a close visual inspection to check for bulging capacitors or burn marks. If you are able to return the motherboard for a replacement I would try that option next.

Thanks for the validation of my hypothesis. The motherboard is coming out next for an inspection of the bottom, top looks good.

 

[Ryan Young]

Well, turns out it was a memory error. I took out my i7 and put it into the problem computer, problem still occurred. I was about to put the i5 into my good computer, when I decided to try to switch out the memory first. Now, I tested the memory before and didn't come up with any errors. The stress test I was using was running Prime95, and simultaneously playing two HD movies. Usually, when opening up the 2nd movie the problem would occur.

I've swapped in two sticks of good memory out of my good computer and my stress test is still running after an hour and a half, with the CPU temps at 80C (it is just a stock cooler and I'm not going to be running Prime95 on a regular basis).

Oh, and as I was moving my new power supply from 120 to 240 I forgot to switch the switch and blew the fuse, so it is running fine on the old PSU!

Thanks for the help and input. Not sure how I could have figured this out other than trying the simple solutions first, i.e.: switching out the memory.

 

[Ryan Young]

Not sure who selected the answer above, but the power supply wasn't the issue...

The computer is connected to a power transformer (240 -> 120) and doesn't have a good ground. Despite a new power supply that didn't fix the issue the computer continues to have random problems, to include shocking me on occasion. I've chalked it up to an unstable source power issue, and am just dealing with it!