Exceeding PSU limits overclocking.

BluD · 31 Jan 2016 at 22:49

Has anyone ever exceeded their PSUs capabilities while overclocking, and what effects did it have?

I was pushing my cards earlier seeing how far they would clock up in GTA and they were running fine at about 1.36v but i think i might have overheated the PSU maybe causing the current to drop a little or summat as my screen went red and the graphics card drivers wouldnt load after i reset so i needed to reinstall them.

Got it running fine again and thought it was maybe just too low voltage on the core so i added a little and tried again. A few hours later i got the red screen again and this time the PC wouldnt post on either bios. I managed to get into the bios after leaving the battery out for a while and reflashed them and got it working again, reinstallled the graphics drivers again and its all up and running again.

The main reason i think its maybe the PSU causing it is cause the only other time i got that red screen crash was when i first got the PSU and i left that Eco mode on so the PSU just overheated after about half an hour all the time, so i had to disable Eco mode to stop that. Also i dont get the same issue if i push one card too far, just get the usual driver crash and artifacts.

Anyone else get any of these results from pushing their PSU a little far?

Jumper118 · 31 Jan 2016 at 23:04

You are pushing that psu pretty hard however it will trip ocp before it overheats. You are probably putting too much voltage through those cards, which I presume are reference cards underwater, so it will be the gpu vrm that is failing rather than the psu. You should keep them under 1.3v unless benching.

Confused Stu · 31 Jan 2016 at 23:09

When I had a 2600k at 4.6 and a pair of 290s at stock (I'm not much of an overclocker), I really wanted to get a higher score on the Sleeping Dogs bench but this pulled more power through my PSU than anything else, especially the indoors scene towards the end. I'd got a wattage meter plugged in and did a few runs. This saw 650W-700W from the wall. My XFX 750W seemed happy, even though the exhaust heat was noticeably warm, and I knew due to it's Bronze efficiency I was still some way from it running at it's rated 750W on the output side.

So, for one stupid now-or-never run, I whacked the clocks and the voltage to the top in Afterburner, made sure it was NOT set to run those clocks at startup and pressed Go.

The bench was running slightly quicker than normal, the air from the PSU was pretty warm, and I just hoped it held on until the bench finished. Then the bench hit the indoors scene. I saw the wattage meter go north of 900W, and the PC shut down. From memory, I think it displayed 914W before dropping to zero.

Switched the PC on, and it happily came to life without a complaint. I set my clock speeds back to normal and the PSU worked perfectly until I got a great deal on a bigger one - it's still quite happily running my mates PC with a 2600k & 7970. Can't decide if I got lucky, or if the Seasonic-made PSU was just very forgiving.

Jumper118 · 31 Jan 2016 at 23:46

Confused Stu said:
When I had a 2600k at 4.6 and a pair of 290s at stock (I'm not much of an overclocker), I really wanted to get a higher score on the Sleeping Dogs bench but this pulled more power through my PSU than anything else, especially the indoors scene towards the end. I'd got a wattage meter plugged in and did a few runs. This saw 650W-700W from the wall. My XFX 750W seemed happy, even though the exhaust heat was noticeably warm, and I knew due to it's Bronze efficiency I was still some way from it running at it's rated 750W on the output side.

So, for one stupid now-or-never run, I whacked the clocks and the voltage to the top in Afterburner, made sure it was NOT set to run those clocks at startup and pressed Go.

The bench was running slightly quicker than normal, the air from the PSU was pretty warm, and I just hoped it held on until the bench finished. Then the bench hit the indoors scene. I saw the wattage meter go north of 900W, and the PC shut down. From memory, I think it displayed 914W before dropping to zero.

Switched the PC on, and it happily came to life without a complaint. I set my clock speeds back to normal and the PSU worked perfectly until I got a great deal on a bigger one - it's still quite happily running my mates PC with a 2600k & 7970. Can't decide if I got lucky, or if the Seasonic-made PSU was just very forgiving.

You didn't get lucky, the ocp did it's job so the psu is still fine

900w out a 750w is very impressive. I think superflower are suppose to be the best. I think 8 Pack had the 1600w pulling nearly 2000w and the 2000w pulling over 2300w no problem

. They might not be very efficient at that kind of output, but still very strong psus

BluD · 1 Feb 2016 at 01:48

Yeah the most i had this pulling was 800watt at the wall, that was with both card at 1.4v, at 1.35v theyre only pulling about 750w normally. I guess your right though, the overcurrent protection would have kicked in and just flat out restarted the machine not given me a red screen if it was pulling too many volts.

I thought its odd though that the only other time i got a red screen was from my 7950s overheating the PSU when i first got it, switching off the eco mode stopped that though.

Maybe rather than the PSU overheating its somthing else in the system, and turning the PSU out of eco mode just kept the other component cooler by its fan been on constantly.

I might have to take a look at the mobo temps or something.

The difference between 1.3v and 1.4 is only 50mhz anyway so its definitely not worth it for general gaming, but what can i say, i was bored and just started tinkering