Voltage drop on 12V rail

[KetoSoi]

I borrowed an 850w PS from a friend so I could do some testing on my system, mostly to compare to the CoolMax 700w I've been using.

I'm curious about what some of you may observed when testing with a multi-meter. On my system (see sig) , at idle, the 850w PS 12v hovers right around 11.90 consistently.

When testing with Burn-In Test, it'll drop to 11.84 give or take .01.

Next test I fire up Dragon Age II and wander around so the GPU can get loaded. 12v sags to 11.75 give or take .01.

Typical behavior, or?

Thanks

 

[Automata]

ATX spec is 5%, which is down to 11.4v. It is normal for the voltage to drop under heavy load and 11.75v is still well within spec. It is fine.

Coolmax is a junk brand, though. You should consider putting in a quality unit.

 

[KetoSoi]

Thanks for the info, much appreciated.

I'm considering buying a 2nd video card to CX, and I'm not sure the CoolMax 700 will handle twin cards, hence the reason I am testing a big-brand 850.

I cant say anything bad about the CoolMax, its been running fine for quite some time, and it maintains its voltages in predictable fashion. But adding a 2nd video card will definitely up the load, and I want to compensate for that rather than hope the CoolMax will hold up.

 

[Automata]

I cant say anything bad about the CoolMax, its been running fine for quite some time

The problem with cheap power supplies is that they save money by putting cheap components in and removing safety mechanisms. So, that power supply may work well up until the point where it fails (which is usually sooner than later). Since there are no safety mechanisms in the power supply, it will have a much higher chance of taking out other components instead of just dying gracefully.

It is always best to get a good power supply. Count yourself lucky it got you this far.

 

[Bobnova]

I strongly recommend getting a Good PSU before you get a second GPU.
You really don't want to put a second GPU in there and then game for 30 minutes before being interrupted by a BANG from under the desk and discover that your PSU has died and taken everything plugged into it with it.