how to check a psu?

Dogfood09 · 26 Jun 2012 at 17:06

Hi all,

After installing a 3tb drive i have been having some random reboots , how do i check to see if my 850w psu is not enough? As i have had advice that my psu is fine and not enough? i can get hold of a multi meter if needed but need advice on what to do with it.

honosuseri · 26 Jun 2012 at 17:12

What spec is your kit? OS and mobo etc

As it's a 3TB HDD some mobos don't like them. Modern mobos have support for them. I will hazard a guess that you need to download a driver/BIOS update to use this 3TB drive for storage.

I'd check this before the PSU myself bud

Video walkthrough for using a multimeter to test a PSU

Dogfood09 · 26 Jun 2012 at 17:35

Im pretty sure my motherboard can handle 3tb, the last thing i done last night was update the bios to its latest version which is eufi.will check to see if it runs ok when i get in from work. Here are my specs

Corsair Obsidian 800D CaseXFX Radeon 7970x2 In Xfirei5 2500K O/C 4.5ghz16gb Kingston RAMGA Z68x UD3H-B3 Mobo Bios f12Xonar DGX 5.1 PCI-E SoundcardCorsair SP2500 2.1 SpeakersCorsair Hydro H100 Cooler120GB Crucial SSD ( System Drive )Seagate Baracuda 2TB HDD ( Storage )Seagate Baracude 3TB HHD ( storage )Dell Ultrasharp U2711 MonitorXFX 850W PSUCorsair 1300 HeadphonesCorsair 2500 2.1 SpeakersRazor Death adder 3500dpi 3.5sg MouseRazorBlackwidow Mechanical KeyboardMicrosoft HD LifeCam

honosuseri · 26 Jun 2012 at 17:46

That's better, now we know what you are working with....Nice rig by the way!

The overclock is going to be drawing more power. I'd suggest running at stock speeds to see if that cures the random reboots. Then gradually up your overclock on the CPU again till you find a stable speed.

If you download the OCCT benchmarking software it includes a PSU test. It will be drawing as much power as it can from the PSU during the test. If you think it's because you don't have enough "juice" that is causing your woes then this test would resolve the theory.

Dogfood09 · 26 Jun 2012 at 19:12

Thanks , I already had put my cpu to stock speeds , Ive disconnected one of my card and it runs fine , but when i connect two , it re-boots.......will try OCCT and post back with an update.

Dogfood09 · 26 Jun 2012 at 19:24

running occt , what am i actually looking for?

Dogfood09 · 26 Jun 2012 at 19:48

http://imageshack.us/photo/my-images/593/2012062619h4133v.png/

I have an error , but dont understand it?

honosuseri · 26 Jun 2012 at 21:40

7970 review with recommended power supply (xfire is 750W minimum)

This test is maxing out power requirements of your installed components. Was this PSU stress test done with both the GPUs fitted?

If so I would remove one of them and try the test again. It's not happy about the 3.3V supply. You see the red spikes? Were the other voltages ok?

If it passes with a single card (flat lining basically on the voltage graph) this means the PSU is failing to keep a constant supply going under heavy load with both GPUs. If you had an overclock on the CPU this would also be asking for more power making things worse.

It would be wise to use a multimeter to see how accurate the OCCT sensors are. However if it's spiking that's not a good sign. You could be asking too much from that PSU it seems

Dogfood09 · 26 Jun 2012 at 21:57

I will post one with a single card usage , and another with both , i only run the test for appx 5 mins if thats ok. Update back shorty.

Dogfood09 · 26 Jun 2012 at 22:15

this is the single card test

http://imageshack.us/photo/my-images/822/1card.png/

and this is in Xfire

http://imageshack.us/photo/my-images/42/2cards.png/

Thanks for your help by the way.

Dogfood09 · 26 Jun 2012 at 22:22

these are at 3.3v

Single Card

http://imageshack.us/photo/my-images/843/1cardsat33.png/

Xfire

http://imageshack.us/photo/my-images/826/2cards33.png/

Dogfood09 · 26 Jun 2012 at 22:48

honosuseri · 26 Jun 2012 at 23:02

Your voltages appear to be in tolerance. Again it would be best to test the PSU with a multimeter to see how accurate the sensors on the mobo are.

PSU voltage tolerances

If OCCT is detecting an error that isn't good. Is your RAM set to the XMP profile in the BIOS? It might not be an issue with the PSU at all but rather your RAM not being at the correct timings and or voltage that's causing the instability.

Dogfood09 · 26 Jun 2012 at 23:10

thats a new ball game for me when it comes to ram.... will check to see if they are in xmp if i can.........

Dogfood09 · 26 Jun 2012 at 23:14

So flatline is good when checking the pc and spikes are not?..

Dogfood09 · 26 Jun 2012 at 23:19

my memory was disabled at the xmp option within the bios , ive now set it to profile 1.

Dogfood09 · 26 Jun 2012 at 23:23

Actually..........come to think of it , i did do my overclock a few days before my issues , and i do remember playing around with some of the ram settings , but once i started to get reboots , i just set the bios to optimized settings , thinking that would set everything to default in the bios? was i wrong in thinking that?

honosuseri · 26 Jun 2012 at 23:28

Dogfood09 said:
So flatline is good when checking the pc and spikes are not?..

It will fluctate a lil bit, it was silly for me to say flatlining to pass but ideally it shouldn't alter too much.

I linked the table that shows the tolerances for each rail, if the sensors are reading right then your PSU is in tolerance. Notice how it idles for a min, the green line kicking up is the CPU usuage. When the CPU gets upto speed the 12V line drops a lil (thats ok still in tolerance) So the PSU is ok it seems

The test isn't just for the PSU but the GPU and CPU. The test has asked the CPU to add 2+2 and its answered 5 for example, which is wrong so it fails. I would look to your memory timings and voltages as I said before and possibly run memtest to make sure there arent any errors. Or run prime95 for an hour or more to see if it fails at all.

Ultimatebootcd is a good download. Boot from it and it has diagnostic tools for the RAM,CPU,mechanical HDDs etc etc...handy disk to have

Dogfood09 · 26 Jun 2012 at 23:32

Thank you very much for your help , I will try that tomorrow after work , thanks again.

Dogfood09 · 27 Jun 2012 at 23:13

Hi , I downloaded the file and booted from it and ran memtest for two hours and it showed up with no errors....