[FXTOi7]

My mosfets are really getting super hot. I have small copper heatsinks on all of them, but when i put my finger over them, i cant hold it down for more than 1 sec or so.

So im in need of a better solution.
Im thinking about maybe stacking another layer of heatsinks over the current ones (yes ghetto) with some thermal adhesive (iv got some arctic silver)

or im thinking about getting a huge mosfet heatsink and pasting it down with some thermal adhesive. makes me nervous that it might fall off and short my mobo.

keep in mind my mobo does not have any holes for installing a mosfet heatsink, so im left with having to basically glue one down.

Any suggestions?

 

[CarlosSpiceyWeiner]

Submerge it in mineral oil. No I"m not joking it really works

Oh nevermind, I see you have it under a rasa cooler already....

 

[FXTOi7]

Quote:

Originally Posted by CarlosSpiceyWeiner;13047384
Submerge it in mineral oil. No I"m not joking it really works

ok ok, something a little more practical.

 

[mdatmo]

Do you have a fan blowing directly over the mosfet heatsinks? Seems like that would be the easiest solution. You could also look into a way of using the CPU block to partially support a larger heatsink. Its out of stock at the egg but you could get something like this and cut it to fit your mosfets.

 

[FXTOi7]

Quote:

Originally Posted by mdatmo;13047503
Do you have a fan blowing directly over the mosfet heatsinks? Seems like that would be the easiest solution. You could also look into a way of using the CPU block to partially support a larger heatsink. Its out of stock at the egg but you could get something like this and cut it to fit your mosfets.

and just use thermal adhesive to paste it down?

 

[scaz]

If you already have a watercooling loop than why not get a mosfet cooler for it?

attached a link:

http://www.frozencpu.com/products/9078/ex-blc-610/EK_Asus_M4A_Chipset_Motherboard_Mosfet_Liquid_Cooling_Block_Kit_EK-Mosfet_ASUS_M4A.html?tl=g30c293s728

 

[FXTOi7]

theres no way to screw in a mosfet block....

http://images.novatech.co.uk/ev-asu-87tde2.jpg

 

[AMOCO]

Just add a waterblock to your loop to cool your mosfets.

 

[AMOCO]

Quote:

Originally Posted by mikepahl318;13047536
theres no way to screw in a mosfet block....

http://images.novatech.co.uk/ev-asu-87tde2.jpg

they come with mounting screws

 

[FXTOi7]

Quote:

Originally Posted by AMOCO;13047542
they come with mounting screws

take a look at the link.

 

[AMOCO]

Quote:

Originally Posted by mikepahl318;13047549
take a look at the link.

well there has to be some way to mount the waterblock,Maybe a full coverage block.if they make one.

 

[hollywood406]

Yeah, stick the largest heatsink that you can get to fit that row of mosfets and put something like an Antec spot-cool fan over them. I can't imagine why Asus would NOT put a heat sink over such a large array of mosfets!

They're usually pretty good about that. I have a huge heat sink over my P6X58D Premium and even one over my M4A89GTD PRO/USB3 and it barely gets warm even under an OCCT stress test.

edit:
One thing to remember, if the heat sink is getting hot, it's doing it's job drawing the heat away from the mosfets.

 

[windfire]

Quote:

Originally Posted by hollywood406;13047594
Yeah, stick the largest heatsink that you can get to fit that row of mosfets and put something like an Antec spot-cool fan over them. I can't imagine why Asus would NOT put a heat sink over such a large array of mosfets!

They're usually pretty good about that. I have a huge heat sink over my P6X58D Premium and even one over my M4A89GTD PRO/USB3 and it barely gets warm even under an OCCT stress test.

edit:
One thing to remember, if the heat sink is getting hot, it's doing it's job drawing the heat away from the mosfets.

I concur with using a fan to supply airflow over the heatsinks. This should be a very effective solution.

See the pic below for an Antec Spot Cool. In the pic, it was not pointing in the right direction but you get the idea.

Also, make sure the hot air would be duly extracted out of the case as well.

 

[Coolwaters]

if u cant mount it then u have to use either thermal adhesive or thermal tape (i recommend the tape cuz u can take that off easier)

im, getting a board soon and looks like the one im getting has no heatsink on the mosfets too...definitely planning on some heatsinks. gpu memory type. or w/e i can find laying around.

 

[FXTOi7]

Quote:

Originally Posted by Coolwaters;13048049
if u cant mount it then u have to use either thermal adhesive or thermal tape (i recommend the tape cuz u can take that off easier)

im, getting a board soon and looks like the one im getting has no heatsink on the mosfets too...definitely planning on some heatsinks. gpu memory type. or w/e i can find laying around.

My 4GHz overclock drops to 1GHz on occasion because the mosfets overheat.... i seriously recommend sending the mobo you bought back and getting one with factory heatsink (if it does not have holes for mounting an aftermarket one)

 

[Andrea87]

Your mainboard runs a 4+1 phase design, which brings some overheating especially if you're overvolting your cpu. Touching a device with your fingers and feeling it really hot probably will mean something in the range of 60-70°C, which isn't at all a danagerous temperature for those things, which are safe up to ~125°C. As you're running water in your sistem, I'd make sure you've got some very good airflow near the fets, and maybe place a good (maybe custom) heatsink there coupled with some good quality thermal adesive pad (akasa ones as example). You can just cut an old cpu heatsink, like a pentium III one, adjust to the right size and use it to cool the fets.

 

[FXTOi7]

Quote:

Originally Posted by Andrea87;13048787
Your mainboard runs a 4+1 phase design, which brings some overheating especially if you're overvolting your cpu.

8+1 phase. but thanks for the advice.

 

[Andrea87]

Having 8+2 inductors doesn't mean at all the board is an 8-phase design. You would need 8x2 fets (which are 4x2 in your case) to have a real 8-phase. They've probably paralleled 2 inductors per phase to keep their current low and under the saturation cap. At least in this board they've used good fets (STM75N20, 75A @ 200V 0.034Ohm), not like msi on some of their boards, which made them go boom under stress.

Get a read there, might be pretty useful to understand vrm's and their problems: http://www.overclock.net/amd-cpus/943109-why-vrms-big-issue-why-choose.html