PSU affecting OC?

[perdomot]

I think I might be having a problem with my PSU that affects my OC but am not sure. Is there a utility that lets you accurately check voltages? I have a Gigabyte P965 S3 mobo and once in a while when I play a video file, the system reboots so I suspect a power issue. Memory and cpu have been tested and they are fine so I need to check the power. Thanks.

 

[MarcVenice]

throw in a overkill psu ? Or check the voltages/amps its putting out and figure out wether your rig actually demands more then what it can put out, but thats quite a hassle ...

 

[simonnance]

check for voltage drops on your rails under load, and use an online PSU calculator to figure out the MAX wattage you could possibly need.

 

[MotF Bane]

Get a multimeter, and a freed four-pin molex, then read your voltages from that.
What's all of your specs by the way, that might help.

 

[Cheex]

Check your system's power draw by going here. It helped me out as well.

 

[perdomot]

Cheex, according to that site, I'm using 511 watts and my PSU is an FSP 500W Blue Storm so that might be the problem. Think I'll look at a 600-700 watt psu tomorrow.

 

[NoSoup4You]

That site tells you what the recommended wattage your psu should be able to handle, not how much power you're using.

 

[VinDSL]

Originally posted by: perdomot
I have a Gigabyte P965 S3 mobo and once in a while when I play a video file, the system reboots so I suspect a power issue...

I don't know if you need more power, per se, but what you described is the hallmark of a *bad* PSU, e.g. your PSU is going bad! After a while, it will quit posting on you altogether.

Might as well get a new PSU, any PSU, before it goofs something up...

 

[lopri]

PSU related trouble-shooting is the most tricky thing, IMO. (Except some obvious cases like where one attemps to run HD 2900 CrossFire with a 300W PSU) It's not just a matter of total wattage, but also individual rails amperage, cross-loads, fluctuation, ripples, etc. all affects system stability. One of the better known symptoms WRT PSU causing instability is a spontaneous reboot in less than 10~15 mins into a heavy load. In general, it's really hard to tell whether/how much a PSU is responsible for system stability, and the easiest way to test it out is to have/borrow a known good quality PSU (such as PC Power & Cooling) and test the system with it. But not everyone can afford such luxury..

 

[myocardia]

Originally posted by: lopri
In general, it's really hard to tell whether/how much a PSU is responsible for system stability, and the easiest way to test it out is to have/borrow a known good quality PSU (such as PC Power & Cooling) and test the system with it. But not everyone can afford such luxury..

There's a way to find out, that's totally free. Just unplug all drives, except the hard drive, unplug all case fans, and remove all cards, besides the video card. If it continues to happen, with everything unplugged/removed, except the processor, video card, HD, and RAM, then it usually isn't the power supply. If it continues to happen, it's usually because of drivers, especially video card drivers; nVidia is known for this issue, while playing back videos, though it usually just dumps you back to the desktop.

 

[perdomot]

I've got a couple of testers going and they both show the +5 rail at 4.92. Is that bad?

 

[betasub]

Originally posted by: perdomot
I've got a couple of testers going and they both show the +5 rail at 4.92. Is that bad?

Slightly low (<5V) but not out of acceptable range. If it holds steady it's OK. It's dips in voltage that you should be concerned about, particularly on the 12V rail when the system (CPU/GPU) is under stress.

 

[MarcVenice]

Like I said, the cpu/gpu AND the HD's all feed off of the 12v rail for most of their power. That's the most important rail to check.

 

[VinDSL]

Originally posted by: MarcVenice
Like I said, the cpu/gpu AND the HD's all feed off of the 12v rail for most of their power. That's the most important rail to check.

True!!!

Personally, I would look for a PSU with a single 12V rail and 35A-ish ampitude!

That should do the trick for 99.9% of the ppl in these forums...

*edit*

Here's a pretty good reference guide!

 

[perdomot]

Is there a utility for measuring the 12 V rail? Speedfan is giving me no reading for it.

 

[grumpyboy]

wicked site thanks

 

[perdomot]

Bump for an answer about measuring the 12V rail. Wonder why it doesn't show in Speedfan. Does the Gigabyte 965P-S3 mobo not do it?

 

[Conky]

Originally posted by: myocardia

Originally posted by: lopri
In general, it's really hard to tell whether/how much a PSU is responsible for system stability, and the easiest way to test it out is to have/borrow a known good quality PSU (such as PC Power & Cooling) and test the system with it. But not everyone can afford such luxury..

There's a way to find out, that's totally free. Just unplug all drives, except the hard drive, unplug all case fans, and remove all cards, besides the video card. If it continues to happen, with everything unplugged/removed, except the processor, video card, HD, and RAM, then it usually isn't the power supply. If it continues to happen, it's usually because of drivers, especially video card drivers; nVidia is known for this issue, while playing back videos, though it usually just dumps you back to the desktop.

Listen to this guy... this is good advice.:thumbsup:

 

[betasub]

Originally posted by: perdomot
Is there a utility for measuring the 12 V rail? Speedfan is giving me no reading for it.

S&M stress test monitors the 12V rail. Useful for seeing how your PSU copes when a 3D app starts up and the GPU goes to work.