MOSFET cooling solution

[neon4]

Hi guys, I wanted to ask if you could help me choose a good MOSFET cooler.
My motherboard is Asrock 990FX Extreme 3 and it throttles my OCed Phenom because of the temps on the MOSFET.
I think I have a good enough airflow in the case, which targets the MOSFETS too, but I also use the CM Hyper 212 Evo to cool down my CPU and it goes in a way a bit after all.
I was thinking about buying a few passive coolers to put on the MOSFET, something like this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16835708011

Does anyone have experience with this kind of thing?
What would be the best cooler if not the one i posted?

(changing the motherboard is unfortunately not an option)

 

[i7Baby]

I like these better - http://www.newegg.com/Product/Product.aspx?Item=N82E16835708008

But same idea. Depends on the size of your mosfet. Just get the biggest that fits. It also helps having a fan blowing over it eg from a case sidepanel fan.

 

[jsmithepa]

Am surprised an "Extreme" board comes with no heatsink over the VRMs.

Enzotech also makes a longest mosfet cooler, looks like it would go over 4 cans and 92mm long I forgot.

 

[neon4]

Am surprised an "Extreme" board comes with no heatsink over the VRMs.

Enzotech also makes a longest mosfet cooler, looks like it would go over 4 cans and 92mm long I forgot.

It actually has a heatsink on the VRM as well as on the NB and SB but it doesn't cool it down efficiently enough, therefore the CPU throtling.
A different approach would be to put a small fan right above the heatsink.
Probably an easier and cheaper solution.
My guess was that the current heatsink is just rubbish.

 

[i7Baby]

I don't think it'd be the VRM heatsink causing throttling problems. Its more likely to be your CPU cooler.

 

[neon4]

I don't think it'd be the VRM heatsink causing throttling problems. Its more likely to be your CPU cooler.

Are you sure? I though the Evo could handle the cooling. But you might be right.
I ran wPrime and these are my temperature results I got from HW Monitor and Core Temp

The CPU underclocks itself when it reaches cca 63 degrees on CPUTIN (this time it got only to 61)

Cool'n'quiet and other stuff controlling this is switched off in BIOS, so I have no idea what underclocks it. Maybe there is a safety controller I can't control on the motherboard.

If the CPU cooling is really bad I'd definately consider replacing it.

 

[i7Baby]

For prime, a CPU at 52C core temp is quite cool. Prime 95 is a torture test.

 

[neon4]

For prime, a CPU at 52C core temp is quite cool. Prime 95 is a torture test.

So what is your idea? What could cause the CPU throttling? If you say this core temp is good for wPrime test, then why does it underclock nevertheless?

I read that the CPUTIN temp is the temp on the CPU surface, not sure about it though and the CPU just undeclocks whenever it goes above ~62 degrees and it doesn't care about core temps being low.

 

[i7Baby]

Its not unedrclcoking. See http://www.cpu-world.com/CPUs/K10/AMD-Phenom%20II%20X6%201090T%20Black%20Edition%20-%20HDT90ZFBK6DGR%20%28HDT90ZFBGRBOX%29.html

Its at 4.0GHz

Why have you got Vcore at 1.5V? Have you been trying to overclock?

Reset bios back to safe defaults and leave it at that.

 

[neon4]

Its not unedrclcoking. See http://www.cpu-world.com/CPUs/K10/AMD-Phenom%20II%20X6%201090T%20Black%20Edition%20-%20HDT90ZFBK6DGR%20%28HDT90ZFBGRBOX%29.html

Its at 4.0GHz

Why have you got Vcore at 1.5V? Have you been trying to overclock?

Reset bios back to safe defaults and leave it at that.

It underclocks itself whenever the CPUTIN reaches ~62 degrees, I see it in the CPU-Z or Core Temp
(200 x20 changes to 200 x4), it is for a few seconds until it cools down itself to ~55 degrees, rinse and repeat. Therefore the throttling.

The CPU is OCed to 4Ghz Stable, any function in the BIOS that has the ability to auto-control the clock speed is turned off.

 

[i7Baby]

Yeah - its getting too hot.

Get rid of the overclock - 1.5V is way too high for 4.0GHz. Reset you bios to get rid of it. Read up on how to overclock your CPU.

Get a better CPU cooler.

 

[neon4]

Yeah - its getting too hot.

Get rid of the overclock - 1.5V is way too high for 4.0GHz. Reset you bios to get rid of it. Read up on how to overclock your CPU.

Get a better CPU cooler.

Well, I had quite a message to post, but I'm not in the mood to argue, I can only ensure you I made large research on how to overclock CPUs before and what to expect with this specicifc CPU. I take your ideas to notice and I will definately consider changing the CPU cooler or lowering my overclock. It doesn't seem to be caused by the MOSFET after all, which I'm glad got cleared out at least. Thanks for your help.

 

[jsmithepa]

What could cause the CPU throttling?

This is quite silly but you are not running in QUIET mode are you?

 

[Mohd Mamat]

Get the Antec SpotCool.Should help cooling the mosfets where normal fans cant reach

 

[neon4]

What could cause the CPU throttling?

This is quite silly but you are not running in QUIET mode are you?

No, turning that off was one of the first things to do before attempting to overclock the CPU

Get the Antec SpotCool.Should help cooling the mosfets where normal fans cant reach

Will check them out
thanks for the tip!