Cooling the Reverse Side of Parhelia GPU?

[DeadAgain]

I'm curious if any of you think this is a worthwile endeavor.

I am hardly experienced in GPU cooling, but I have been seeing heatsinks that cover the front and back of PCBs lately, the most prominent being the Zalman HeatPipe cooler assembly.

Well, I was wondering, is it a viable solution to have active cooling on the GPU and the PCB behind/underneath it? The area back there is defintely hot to the touch, so I have added a passive Northbridge copper cooler just to see if it would get hot also. It does.

I'm thinking about adding a copper sink and fan (Vantec GPU solution) now to see if this helps aid heat dispersion. But who knows, maybe this will actually do the reverse. I stayed home the day they taught thermodynamics.

Thanks!

[Taz]

The reasons for the Zalman using both sides of the graphics card has more to do with the heat pipe design rather than the need to cool the back of the card

[UtwigMU]

The heatpipe transfers heat from the bottom side using liquid to the upper side where it can disperse on larger surface, thus taking the heat away from the core.

In a fanned design, airflow takes away the heat, so there's little need for large heatsink to disperse heat.

[DeadAgain]

Thank you both for taking the time out to explain the Zalman. I understand its operation.

I was asking if anyone had any thoughts on actively cooling both sides of the GPU, and furthermore, if anyone had done this and achieved high stable overclocking.

[dZeus]

yeah, I've got the Zalman ZM80A-HP on my Sapphire 9500 Pro, and the back side doesn't touch the PCB at all... all heat is transferred through the heatpipe (which works rather well, since the back side heatsink heats up considerably in operation).

I don't think cooling the back side of a videocard is an easy endeavour, since there are lots of SMD components around/on the back of the PCB at the position of the graphics core. Too much pressure applied on them and they might crack/come loose from the PCB.

[UtwigMU]

With most graphic cards PCB is between core and back side. Therefore it would be ineffective.

Stock cooling is sufficient for normal operation and if you want some extreme cooling, watter cooling or heatpipe with well ventilated case should be much better than most extreme heatsinks placed on parts where there is much material between core and heatsink (RAM, back of PCB).

[rylan]

I have a small Fansink cooler that I attached with thermal epoxy to the backside of my G400MAX. The back of that card got pretty warm behind the GPU, and it let me overclock it a little more. I'd assume you would see the same result on the Parhelia, since its definately core-limited for overclocking. Cooling on top of the chip is more efficient, but there is enough copper in the vias through the pcb to sink quite a bit of heat from the chip if you attach something to the back also (as you saw with a passive heatsink).