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causticVapor
11-12-2002, 10:37 AM
Finally the koolance case came in!
After two months of waiting!!!

As you can see, I've recently upgraded my rig to that with koolance water cooling, the PC2C to be exact; the CPU-200S block was used. The CPU averages around 31 degrees celsius at 33 degrees load! My Ti 4200 is also in the chain, and can go 10% faster.

Noise is also lowered substantially.

The only problem with this is that there is very little air circulation in the case, even though I have an 80mm exhaust fan. CPU overclocking has been hindered by the fact that the three MOSFETs on the top of the board, as well as the coils, are extremely hot. This is an unfortunate byproduct of a fan not blowing air on top of it.

I know some motherboard manufacturers have placed heatsinks on their power supply areas, but then again I heard from THG that good quality power supply components don't need heatsinks. :confused: My DIMM voltage is at 2.9V; I don't think it should make that much of a difference.

Could this high heat be caused by the fact that I have four PCI cards installed? (controller, NIC, modem, Audigy) that consume about 30W each... Is my PCI bus power demand stressing the MOSFET components?

The 8KHA+ has three on the back as well, so that might compound this dilemma.






All I know is that I can O/C much better with a small fan blowing above the MOSFET area; my theory is that the overheating mosfets deliver attenuated, chopped up electrical signal, which is detrimental to the high-purity demands of OCing.

NDD
11-12-2002, 09:50 PM
All I know is that I can O/C much better with a small fan blowing above the MOSFET area; my theory is that the overheating mosfets deliver attenuated, chopped up electrical signal, which is detrimental to the high-purity demands of OCing.

Sounds very logical :)

"Good Cooling" is the keyword :)

causticVapor
11-15-2002, 11:18 PM
HMM.. VRM and condensors not overheating now with no air circulation at all. :confused:

Still, random reboots.



..but alas, the problem has been isolated: A faulty transformer is the culprit! I'm switching over to a new 2200 watt one when I get the chance. :D

Giblet Plus!
11-16-2002, 01:39 PM
I've heard of people putting heatsinks on their mosfets. It usually makes the core voltage a little more stable. :)

causticVapor
11-17-2002, 12:42 PM
Yep, that's what I'll do

Thermal adhesive + BGA sinks from frozenCPU.com onto them
And then heatspreaders on the back mosfets...


the only way...

Giblet Plus!
11-17-2002, 02:55 PM
Tell us how it works. :t