[Solved] Can a fried motherboard kill new PSUs?

Forum CPU & Components : Power Supplies, Cases & Mods [Solved] Can a fried motherboard kill new PSUs?

I decided to replace my old PSU (an OCZ GXS700) because it was causing the computer to spontaneously restart after shutdown. The first PSU I tried was an (Edit: Antec, not ASUS >.> ) New TP-650. This worked fine in terms of power, but I returned it because it made a loud clanking noise when turned on. I then decided to try out the NZXT HALE82 750w. However, when I plugged it in and turned it on, the PSU kept dying during the boot up (it basically turned off and restarted continuously). I took it back to the shop, where they confirmed that it was dying with a multimeter. I got the same model as a replacement and brought it back, but it had the exact same problem.

I was pretty confused at this point and thought that maybe some other components in the computer were frying the PSUs. I tried plugging in the old GXS700, and it completed the boot and got to the desktop without problems, making me think that all the other components were fine. I then brought the second HALE82 back to the shop to get it replaced. The tech guy then told me he thought that my GXS700 had messed up my motherboard, and the motherboard was blowing the new PSUs I was plugging in. If this is the case, then why the GXS700 still powers the computer on is beyond me.

Sorry for the long read, and thanks for making it this far. I want to know if it's actually possible for a bad motherboard to kill the PSUs. The only weird thing is that if this was the case, the GXS700 shouldn't work either. Also, they still had the TP-650 that I returned, and it still worked fine when they plugged it into their multimeter.

Is it possible that my motherboard's broken, or did I just have incredibly bad luck with PSUs? The motherboard is an ASUS P8P67 Pro, if it's relevant.

Again, sorry for the long read, and thanks for taking the time to help me out!

Message edited by Dragonarion on 02-13-2012 at 04:52:02 PM

Reply to Dragonarion

Not sure if it's the motherboard killing your PSUs as much as it is the brand of PSUs you are getting.

For the sake of being thorough, what are the rest of your system specifications?

------------------------------ If all the animals along the equator were capable of flattery, then Thanksgiving and Hallowe'en... would fall... on the same day.
Reply to hpdeskjet

Actually you are using good to very good power supplies. The NZXT Hale is not great but is pretty good and the Antec TP New is quite good.

http://www.eggxpert.com/forums/thread/323050.aspx

That is an odd problem for sure. Sounds to me like the motherboard is damaging the power supplies. That or you have the worst luck in the world

It is possible for a motherboard to kill a PSU but it is very odd only the 2 NZXT units would not work at all. I think I would RMA the board just by default. I don't know though since it works with your old known good power supply.

------------------------------ i7 2600K @ 4.5/P67A UD4/Scythe Mugen 2 Rev B/OCZ Vertex 2 120GB/2xWD 640 Blacks/Antec 1200/Samsung 23in LED LCD/EVGA GTX 460/2x4GB GSkill Ripjaws X DDR3 1600 7-8-7-24/Windows 7 Ultimate x64/Corsair 750TX
Reply to anort3

*facepalm* I actually thought that was an ASUS PSU from the OP, which was weird since I've never come across an ASUS PSU before :pt1cable:

Anyway, sorry for any confusion. I'm not one to doubt Antec PSUs since I'm using one. Didn't know about the NZXT unit being a decent one. Good list to have. Thanks.

------------------------------ If all the animals along the equator were capable of flattery, then Thanksgiving and Hallowe'en... would fall... on the same day.
Reply to hpdeskjet

Best answer

Today's PSUs are very secure in terms of shortings. They have lots of fail safe solutions that prevent the PSU from dying a horrible and quick death. Even if you short a couple of terminals and try to switch it on, good quality PSU's will not even try to power on. Therefore I highly doubt it your board alone is killing the PSU.

Reply to darkguset

I think you just got a round of bad luck.

Reply to memadmax

you could test the PSU's for a while - soak test them with a Test Plug.
http://www.duxcw.com/faq/ps/ps4.htm
Soak Test leave it running for a good few hour normally i would say 24Hr but as long as is practical. Just to get it though the fails in the first few hours phase.
It would be better to test it under some kind of load but this is difficult to simulate at home unless you really have to.
When you first plug it in to your motherboard ONLY plug in what you need to boot to BIOS screen. ONLY add cards you need - eg on board VGA? eg Mother board and one stick of ram.
Note you only need to hear the BOIS post beeps at first. Then go for VGA card, then after a few hours on the BIOS screen (health page is good to view at this stage).
If all is ok then start pluging your main drive in. i have had issues with poor PSU blowing CD drive when writing disk so after you Primary drive then CD drive. Write a full CD to test PSU voltage integrity. Writing a CD need a very stable PSU paticulaly if that PSU is close to its design limit.

hope that helps.

Reply to davidgermain

Hi everyone, thanks for all the replies.

I tried a 3rd PSU (NZXT HALE82 850w) and, while the PSU didn't seem to die, it consistently took two tries to boot to desktop. Turns out that my i5-2500k's BCLK was set to 103 instead of 100, which apparently causes instability. Now I'm wondering if the other PSUs were in fact defective - although I think they must have been, since they failed a multimeter test after all. What beats me is why my old GXS700 apparently had no problems booting even with the instable BCLK :\.

In any case, I reset the BCLK to 100 and everything's running like a dream now. The 850 watts also gives me an excuse to add some more HDDs and a second video card, lol.

Thanks for all the help!

Reply to Dragonarion