Asus A8N-SLI Premium and watercooling, chipset + pipe = too hot ?

Watercooling for the CPU and GPU, but what about the chipset ? Is it safe with only the pipe ??

it's freaking hot !!!

i don't think it's possible to install anything else, my video card is ASUS 7800GTX and it's too long.


thanks

 

You don't have the motherboard mounted with the heatpipe running
downward to its heatsink do you? (Some cases like the Lian Li V1100
and V2100 required the motherboard to be mounted upside down relative
to conventional cases.) The heatpipe cannot work in that position.

Several owners have reported chipset temps that they feel are
alarmingly hot. It's difficult to reconcile that finding with
situations like mine where I have to touch the chipset for several
seconds to even tell if it might be warm. I think that when the
board's mounted properly and the heatpipe is working correctly, the
chipset will be bordering on "cool." Therefore, if the board's
mounted in the conventional position, and the chipset is "freaking
hot," I'd be a suspicious of a manufacturing defect, namely, over- or
underfilling of the heatpipe with "refrigerant."

Ron

 

ASUS 7800GTX and it's too long.

One thing to point out. The heat pipe on the Premium, moves the
heat from the Nvidia chip, up to the MOSFET heatsink. To work
properly, there MUST be air blowing over the MOSFET heatsink.
That is the heatsink next to the CPU.

What Asus is expecting, is you have a "normal" fan on the CPU,
and some air from the CPU fan "spills" onto the fins of
the MOSFET heatsink. That moving air over the MOSFET
area should be enough to bring the temperature of the
heatpipe down considerably.

Now, consider a couple of other possibilities. You can buy
aftermarket "tower" style coolers. These blow the air sideways,
and the CPU cooling air is no longer pointed at the MOSFET
cooler. Such a tower cooler would be a poor choice for
the Premium.

If you use water cooling for the CPU and video card, there will
be NO moving air over the MOSFET heatsink. Install a fan of
some sort in the vicinity, to provide that moving air. Set it up
to blow the air through the fins.

The heatpipe can only move the heat somewhere. It doesn't
eliminate the eventual need to transfer the heat to the
surrounding air.

Paul

 

thanks... now must a way to install a fan... my case is the Thermaltake Aluminium with no side hole..


any idea ?

 

I have used a couple of techniques to mount fans. I've used an
aluminum bar with an "L" shaped cross-section. I think it is
sometimes called "angle iron". I drilled a hole in one end,
and pushed a PCI slot screw through the hole, and fastened
the aluminum to a PCI slot. This gives you a piece of
material to work with.

Here is a commercial equivalent, only it may not reach far
enough to place the fan over the MOSFETs. I don't see any
dimensional drawings on the web page, to allow me to figure
out how far it reaches.

http://www.zalman.co.kr/eng/product/view.asp?idx=15&code=

I've also used nylon "ty-wraps" to fasten fans to things.
Find a ty-wrap which is small enough to fit through the holes
in the fan. If your computer case has a cross-bar, you can
secure a fan to the cross-bar with the nylon fasteners.
(These are the same kind of fasteners that are used for
keeping bundles of cables neat and tidy - you can get them
at a hardware store or electronics store).

It can be really difficult to find mounting points for
unconventional things, inside a computer case. You just
have to be creative.

You don't have to draw cooling air from outside the
case for this cooling application. All you need is to
get a flow of air over the MOSFET cooling fins.

Sorry I cannot be of more help, but this is one kind
of problem where you have to be there in person, to
find a solution. Virtually any extra screw holes in
a subassembly in the computer, can be used as an
anchor point. I don't like drilling holes, unless
I know in advance it will be necessary, and can
vacuum out the case after the holes are drilled
and any metal burrs are removed from around the
holes. You don't want metal filings floating around
inside the computer case.

Paul

 

thanks I did find another solution too... http://www.xoxide.com/sunbeam-wherever-pci-rack.html

But I really wonder if it's necessary...Of course it become vey hot but what are the thermal spec of the
chipset ? My guess it's made to sustain very high temp.

jean-

 

Also, before going to all the trouble of finding a means to
fasten the fan, plug in an 80mm fan to one of the fan
headers, and just hold the fan over top of the MOSFET
heatsink. See if the air from the fan, when blowing over
the MOSFET area, causes the heatpipe to cool off. If, as
Ron suggests, the heatpipe is defective, it could be that
the fan won't do anything. My presumption is that the
heatpipe is working, and just needs some cooling air
at the destination end.

To give you an example I've run into. I had a computer with
a passive heatsink on the Northbridge. I got a digital
thermometer from the computer store, and it measured 75C on
the fins of the Northbridge heatsink. That means the silicon
die underneath the heatsink could be running at 100C. When
I placed a 40mm fan over top of the heatsink, the fin temperature
dropped to 37C. That is a pretty good temperature drop for
such a small fan.

Paul

 

< hot but what are the thermal spec of the

That is an excellent find Now I won't have to buy any
more aluminum angle iron, to make my own framing.

The commercial chip temperature operating range is 0C-70C.
At 55C, you can only hold a finger on the surface for a
second or two. At 70C, for a little less time. My own
personal (not based on science) preference, is to not
let anything get hot enough to burn myself on. The silicon
can take the heat, and you will likely replace the motherboard
before the component reliability is affected.

Consider conditions inside some of the DTR laptop computers.
The chips in there are continually roasted, and yet the laptops
seem to last.

In a computer, the most important thing to keep cool is the
disk drive. Its temperature rating is not very high at all.
Hard drives are affected by both temperature and humidity, so
if the room air can be kept dry, the temperature is allowed
to go a lot higher. After the disk drives, any electrolytic
capacitors are the next thing to keep cool. There are some
of those next to the processor. There are two big ones, full
of energy, inside the ATX PSU. Keeping the caps cool, helps them
to meet their 10 year life expectancy. Even with water
cooling, there are still reasons to have cooling air moving
through the computer case.

Paul

 

thanks.....I let you know what I fianlly did... maybe it will be another waterblock for the chipset ;- )

 

I finally find a solution this morning.... It came from nowhere : -)

reply to I will send you a picture.


Bye