PSU voltage question

[unix443]

Hi.
I have a Corsair ax1200 PSU. It's only around 12months old with 6months use in it.
I was running OCCT last night. Done a 29 hour line pack test. Noticed it said 12v Minimum 12.0v. Thought that was strange never seen that before.
Done a quick PSU test using OCCT 12v dropped to 11.8v.
Loaded a game in 3d vision voltage was at 11.9v. Even at idle I noticed in the graph is will drop to 12.0v occasionally.
Opened HWiNfo64 OCCT Aida64 each program exactly the same voltage.
I know people say use a multi meter but 3 software programs and in bios for idle voltages give correct readings. I cant use a multimeter as my PSU is in an awkward position my bottom GPU outlet hose is in the way so to test it I have to drain my loop.
I know their not huge drops but the whole reason I got this PSU is that it can handle quad SLI etc. With ought dropping 12v on the rail. Supposed to be a quality PSU. e.g.

" DC Load - 1204W - +3.3V - 3.25 - +5V - 4.95 - +12V - 12.02 - +5VSB - 4.94 -12.30".

If I added another GPU I doubt it would even boot. So I'm thinking this thing has to be degrading or defective. But I thought id ask some of you fine people what your thoughts are.

Also a while ago I modded my GPUS bios and could add more voltage.
I had the clocks up to 1200mhz no crash or anything just started getting flashing black lines across the screen during HEAVEN. I thought it was just the limitations of my GPUS, Even if I added more voltage it kept doing it. Now I'm half wondering if the voltage was getting to low.

I have done some reading and know ATX claim 5% -/+ is acceptable. But for me this PSU should not Be going under 12v with only 2GPUS and an overclocked I7.

Thanks in advance.

 

[Adroid]

Well, to know for sure.... Use a multimeter. I know that's not the response you are looking for, but typically that's how you get the most accurate readings.

With readings that close using software, I personally wouldn't worry about it. Electricity has never been, nor will be, an exact science. I don't know what GPU you are running, but I'm sure you can run a 3rd one without trouble.

Black lines across the screen is undoubtedly resultant of pushing the GPU clock too far, not the signs of a defective PSU.

If the PSU makes strange noise, or gives crashes, then yes, your PSU may be defective. If everything is operating normally besides the lines through the screen when overclocking I would not worry about the PSU. If you have strange crashes or reboots under load, then I would check the PSU. You can always RMA it and Corsair has a great warranty policy, but I think that would be alot of wasted time and effort to find out it's operating under normal tolerances.

 

[unix443]

Hi.
Thanks. I have dual 780 sc. Flashed bios with 1137mhz stock. What I was trying to say is I can do these clocks on 1.152v. No artefacts or crashes. If I set them close to 1200mhz I see these lines, still no crashes or anything even if I pump 1.12v through them these lines remain.
So they should be good for way more than 1200mhz if I can run 1137 with only 1.152v.
But anyway. I just ran Heaven benchmark checked OCCT +12v minimum went down to 11.71v. Now I cant work out why this has just started happening.
Also Heaven my GPUS arnt sitting on 99% usage. One goes 96 - 98 - 80 sometimes 99. Seems strange also.
I have a brand new the same ax1200 sitting in a box over 12month's as an RMA on a defective on/off switch from my last one. Looks like I might need to change the thing I guess.
The psu makes a weird noise when the system shuts down but cant hear anything while its running.

 

[Zerk2012]

Hi.
Thanks. I have dual 780 sc. Flashed bios with 1137mhz stock. What I was trying to say is I can do these clocks on 1.152v. No artefacts or crashes. If I set them close to 1200mhz I see these lines, still no crashes or anything even if I pump 1.12v through them these lines remain.
So they should be good for way more than 1200mhz if I can run 1137 with only 1.152v.
But anyway. I just ran Heaven benchmark checked OCCT +12v minimum went down to 11.71v. Now I cant work out why this has just started happening.
Also Heaven my GPUS arnt sitting on 99% usage. One goes 96 - 98 - 80 sometimes 99. Seems strange also.
I have a brand new the same ax1200 sitting in a box over 12month's as an RMA on a defective on/off switch from my last one. Looks like I might need to change the thing I guess.
Software is not accurate unless you use a volt meter your wasting time. You not going to get a steady 12 volts out of anything.
The psu makes a weird noise when the system shuts down but cant hear anything while its running.

 

[Zerk2012]

Your wasting time software is not accurate. Your not going to get a exact 12 volts out of anything.

 

[unix443]

Well I have a brand new ax1200 here that was a replacement from Corsair for my last one where the on/off switch failed.
All I know is if the software was reporting it fine a while ago now its not across three programs and bios surely that's got to be half accurate?.
I think I'm gonna just put this other PSU in tomorrow. How can I test a PSU with a multimeter when its under load?.