MSI K9A2 CF-F Mosfet Cooling

[Russ_64]

First off, if you are researching this MB for AM2/AM2+ CPU then BEWARE - it does not support 125w CPU (currently 6000+, 6400+ X2's and FX62). It does support Phenom 95w but may have issues if you plan to OC as there is no cooling on the Mosfets (as you can see below).

I was planning to cool them but the Thermalright HR-09 will not fit and there are no waterblock available (yet). So I guess that leaves the Microcool Heatsinks (I have 6 of them that I used before, so better than nothing).

Anyone have any other ideas ?

[madfaze]

hmmm i was thinking of a ramsink instead...
or a coolermaster chipset cooler...

[Russ_64]

Chipset cooler is 37mmx37mm - wont fit on Mosfet.

Microcool Southsink dissipator: 15(L)x12(W)x18(H) mm, RAM sinks will also work but they don't have as much height.

Also, I am replacing NB and SB MSI heatsinks with Zalman NB47 and NB32 coolers.

[Jakalwarrior]

Before mine went up in smoke, I was going to order some long ram sinks to cover 3 at a time then count on that noisy high cfm triblade fan on my XP90 to do the rest.

Something like this http://www.performance-pcs.com/catal...oducts_id=1658 8 dollars for 8 copper ones. Would probably only take about 4. Use the rest on on stuff like the pll etc... or save em.

Without the thermal pad though. That thing looks too thick. Lil ceramique or something since they look to small to do the as5 / superglue thing efficently.

[Russ_64]

Yeah, RAM sinks are a bit small IMO.

These look better (and I can get them in UK):
http://www.performance-pcs.com/catal...ducts_id=21214

I already have Akasa Thermal Adhesive Tape to mount them.

PS - what CPU were you using? Did you increase any voltages?

[Jakalwarrior]

Yeah I did increase voltages. Was a 4000+ 65nm at 1.49 for about 1 hour before it let out the magic smoke (playing WoW not priming). Ram was at 2.2. Its down the forum a ways (maybe on second page) with pics etc...

I dont think sinks woulda saved mine :/

[GD5015]

Bit-techs review shows the x2 6000+ running just fine. Wonder if maybe it is more isolated than it seems here?

http://www.bit-tech.net/hardware/200.../msi_k9a2_cf/1

[Jakalwarrior]

The only chip they stress tested with was the 6000+. May have been the 65nm version, which this board does support.

If they repeated the stress test with voltage at 1.5 I would say it was just two flukes on or forum has to be some sort of reason the board doesnt support any chips higher than 89 watts. Until we find out why, people should think twice before overclocking your chip past the wattage of the 6000+ 65nm (max chip it supports).

*edit. According to a lil web calc I used, my chip was at 133 watts.

[Russ_64]

I was going to say that there are 2 versions of the 6000+ (one is 125w and the other is 89w - they don't say which they used and most buyers would not know which they have?).

Anyhow, I found this interesting:
"Cooling
The board uses some very simple heatsinks, but thanks to the 790X north bridge and SB600 south bridge being so cool, that is all that’s necessary. Even after hours of load, the north bridge barely gets warm to the touch. The CPU power regulation components don’t get any extra cooling though, which means all that heat is left to circulate around the chassis and back into the PCB. Interestingly, there are a couple of pin holes to mount an aftermarket (or self made) heatsink solution if you feel the need, but even after hours of load they didn't really get hot enough to cause concern."

They also tested a P9900 (2.6 - I assume a ES - don't know if it is also 95w??) no problems reported = Good news!

[Manicdan]

i just keep my old cpu heatsinks and make my own with a dremel. works every time. too bad i was one of the first with the problem and didnt have time to prepare for it.

and btw thats wrong about the northbridge being cool to the touch, thats way off. i kept a fan on mine cause after just a few minutes it was close to burning you if you touched it.

[madfaze]

any development?

[Russ_64]

I just received my SB heatsink today (already had the NB and Mosfet sinks). Will be building this weekend and will post pics. Consensus seems to be that mosfets don't need major cooling just decent airflow and this MB does not like overvolting therefore Phenom at 1.2 - 1.25 should be okay.

[madfaze]

I just received my SB heatsink today (already had the NB and Mosfet sinks). Will be building this weekend and will post pics. Consensus seems to be that mosfets don't need major cooling just decent airflow and this MB does not like overvolting therefore Phenom at 1.2 - 1.25 should be okay.

cool looking forward to it mate!

[madfaze]

any news?!

[Leeghoofd]

Main wasn't even build in , beefy 120mm blowing straight on them, they were slightly warm , pc shutdown suddenly during software install, rebooted straight away, 30 mins later shutdown completely...no visual damage but baord was dead... I really think it's a bad design or flaw in some components though more and more get these issues... it was equiped with an 6000+ 89watt version , Bios 1.1, 2 gig of ram PC6400 and an ATI 3850 256 vidcard, OCZ 600 watt PSU... hope your boards are more durable, budget asus in this rig and that has run flawless for over 5 days now (while it seems more fragile then the MSI : smaller NB heatsink, fewer mosfets,...)

[Russ_64]

No - the Zalman NB32 was too big for the SB600 - it blocks the 2nd PCIe (and I may want to add 2nd HD3850 later) so I ordered a Microcool Southsink and a few more Mosfet Coolers but I am still waiting for delivery (after 1 week).

I ran my MB twice for a day each time and did Sandra benchmarks but did not OC. Hoping that my MB is a "good" one, there are now at least 5 that have died!

[Jakalwarrior]

Just hope all your cooling work doesnt get scorched by the flaming mosfets

Wish MSI would do something to make it up to us. Like... atleast pay for the RMA shipping charges or give us a plat for free.

[GD5015]

Have had mine running for about 2 weeks now. 5400+ (65nm), 3.2 GHz @ 1.382v, bios v1.2, Tuniq tower,, 2 gigs Adata 5-5-5-15, MSI 3870 OC, and Earthwatts 500 power supply. No problems so far with got 6 120mm fans and a 70mm fan blowing on the underside of the cpu socket, in a CM RC690 case. My mosfets get just warm to the touch, cpu temps on the board are 40c under load with 38c on the motherboard, according to hardware monitor v1.06. So far I couldn't be happier. I plan on trying some homemade heatsinks on the mosfets before the weather gets hot.

[luckskywalker7]

Hello all, I just recently got one of these boards along with a x2 4000+. If just increase the FSB and not the Voltages would I be ok to not get any mosfet cooling?

[RCRacing]

MSI K9A2 CF-F, Havin trouble getting the 1066 with this board for the ram.It shows as 800fsb.try switchin and go back to 800.I have the Kingston Hyper X 2x512/1 gig.Anyone with ideas.MSI keeps sending me this new bios,however am unable to flash bios.

[madfaze]

MSI K9A2 CF-F, Havin trouble getting the 1066 with this board for the ram.It shows as 800fsb.try switchin and go back to 800.I have the Kingston Hyper X 2x512/1 gig.Anyone with ideas.MSI keeps sending me this new bios,however am unable to flash bios.

how come?were you using the usb drive in updating?what version did they give you anyway?

[KTE]

First off, if you are researching this MB for AM2/AM2+ CPU then BEWARE - it does not support 125w CPU (currently 6000+, 6400+ X2's and FX62). It does support Phenom 95w but may have issues if you plan to OC as there is no cooling on the Mosfets (as you can see below).

The main issue is not the cooling, the issue is what causes the overheating.
The VRM supply circuitry of that board cannot handle the current generated by overclocking Phenoms or by the high TDP chips. I'm not sure what it's regulated to exactly but the limit is near 80A including NB which needs it's own current supply from the regulator, but Phenom can and will pull upto 110A CPU and 20A NB when overclocking. By trying high volts/MHz, people will burn up things quick.

[Daveburt714]

This might be old news, but MSI finally admitted to the problem (sounds like you already knew Russ )

http://www.bit-tech.net/news/2008/01..._the_k9a2_cf/1

Makes me wonder it this same problem doesn't lead to some of the instability issues on it's big brother, the K9A2 Platinum....

[Russ_64]

Yeah, hopefully I will be okay with Phenom and I will definitely only OC at stock volts.

I have installed the Microcool Mosfet sinks and Zalman NB HS but all the SB sinks are too big/chip is too small even for Thermal Adhesive so I have replaced the MSI one with pins. Watercooling is now in and leak tested, so final install of components is finally in progress. Will post up some pics asap.

[madfaze]

Yeah, hopefully I will be okay with Phenom and I will definitely only OC at stock volts.

I have installed the Microcool Mosfet sinks and Zalman NB HS but all the SB sinks are too big/chip is too small even for Thermal Adhesive so I have replaced the MSI one with pins. Watercooling is now in and leak tested, so final install of components is finally in progress. Will post up some pics asap.

nice! looking forward to see those pics..


@all

anyone who knows how to read the temps on those NB chipsets?