5870 fan slowing down as load increases

[smithy95]

Hey guys just stopping by to ask your opinions and advice.
Basically the situation is that as I place my graphics card under any heavy load the fan will start to slow down until it eventually stops, at the moment I have the fan set to manual 40% and running at roughly 2800 rpm.
i load up a game like burnout paradise, the graphics card cranks up to full power to take the graphics demands of the game and on my g13 screen all i see is the rpm speed steadily drop and the temperature rise more and more as I continue playing until the fan just stops and the temp goes from something acceptable (roughly 40-50C's) to mid 90s.
Now my suspicion is that it's my PSU (some cheap 500w PSU I believe) and this problem has only just occured after I installed a core 2 quad 8300 in my system.
As it stands my system specs are:
HD5870
Core 2 Quad 8300
4GB RAM
X-Fi Titanium PCI-E
I'm looking for a quick answer to this guys so any opinions and help would be greatly appreciated, even more so the sooner it comes but is my suspicion likely to be correct in that my PSU just doesn't have enough juice to give to my whole system under that kind of load and that I need to upgrade or is it something else all together?

 

[-Fran-]

It could be a problem with the fan itself, or it could be a driver issue. I doubt the PSU has something to do with the fan slowing down while the card is actually being used at load, thus being supplied with power. It could be that the PSU is not giving a constant amperage to the card... That could damage it. Can you get a second PSU or something to test? and what Catalyst have you installed?

Cheers!

 

[smithy95]

Thanks for the quick reply, the fan itself works fine, when the card is sitting idle or in any power state other then full tilt (850/1200) or there abouts the fan speed remains constant, it is only when the voltage increases to 12V that the fan starts slowing down, I don't have a second PSU at the moment to test with but have been looking for a reason to get a new one as my current one is now roughly 3 years old and probably doesnt output the 500W rated power anymore anyway, as for catalyst drivers, I have the latest ones.
At first I didn't think it was the PSU and that it was just the drivers, until I turned my computer off, shined a torch through the side of my case at my graphics card fan turned my computer back on and still had no fan, only after leaving the computer turned off at the plug for about 10 minutes then turning it back on did the fan work again.
As I said though, the problem has only started since I installed my core 2 quad which under load draws more in the way of power then my old core 2 duo e4500.

 

[-Fran-]

Can you spend like 40-50 bucks for a new PSU right now?

If so, get a new one IMO. It doesn't hurt at all having a good quality PSU.

Brands to look for would be (IMO, that is): Antec, Corsair, Thermaltake (have an eye on efficiency). Around 400w+ with 24A combined on the +12v rail.

Cheers!

 

[smithy95]

Thanks again for the reply, as it stands I can't get another PSU until Friday and even then I have to wait for delivery as none of the computer stores in my area stock reliable and reputed brands for a decent price, I do have one in my sites though http://www.ebuyer.com/product/127861 (hoping you're allowed to post links, if it get's deleted then it's a OCZ stealth Xstream 600W for £55)

 

[-Fran-]

For the specs I read, it's a solid performer: 80%+ Efficiency, PFC and 72A on the +12V combined. That would be a really nice buy.

At least that would give you the answer right away if it was the PSU. I suggest you order it (unless someone else has a better suggestion, that is) and wait till it arrives.

Cheers!

 

[smithy95]

Thanks for the help, I'll get it on order ASAP, I just hope that for once the problem is the most obvious one.
If anyone has any other suggestions then I will still be glad to hear them any help and advice is appreciated as always

 

[smithy95]

Best answer selected by smithy95.