Help with thermal pads

[scrumdiddly]

I just bought 3 of these thermal pads to slip between my waterblock and graphics card mosfets, but I have no idea whether I'm supposed to remove the backing from them. There's no info on the site itself: http://www.scan.co.uk/Product.aspx?WebProductId=718555 and the Alphacool site doesn't seem to have any mention of them.
I'm asking because I've already pretty much ruined one of them trying to take the backing off. It just won't budge without taking half the pad with it!

The pad itself is extremely soft and sticky, and the backing is some kind of fibre and is not sticky. That's why I'm assuming it has to be removed. Aren't these things supposed to stick down?

Help!

 

[Putz]

i think the fibre holds the thermal material in place

the only stuff ive seen with a backing is the gel based thermal pads, and that backing on them keeps it flat and from tearing, pads aren't sticky there just to fill the gap and transfer heat between 2 things

 

[Putz]

found this on a quick google search


ThermaSoft, the Next Generation of Thermal Gel Pads
A PROBLEM YOU HAVE SURELY MET: Gap filling products consist of a fiberglass cloth substrate coated with Silicone gel, or they are polyurethane foam that is impregnated with Silicone gel. The reason for this is that the Silicone Gel material is not cohesive enough by itself and requires mechanical reinforcement. When you deform these products they initially conform easily to surface irregularities. However as you continue to deform them, the fiberglass cloth or polyurethane foam prevent further deformation. Increased pressure on the material no longer results in deformation. This means the ability of the pad to conform to surface features on a circuit board is severely limited. As one frustrated thermal designer expressed it: “It’s like running into a stone wall.”

WE FOUND A SOLUTION: ORCUS created ThermaSoft, the first self-supporting silicone gel pad that requires no reinforcement. Therefore it is eminently deformable. This means it can be compressed much more than other gap filling materials. The result is that ThermaSoft can wrap itself around components much better than other products, and that means better heat transfer. So, it fits both engineering and manufacturing requirements, allowing you efficient use.

ThermaSoft is available as die-cut parts and in standard sheet size of 8”x 8”. It can be supplied in thicknesses from 0.5mm to 7mm. Thermal conductivity of ThermaSoft is 1.0 W/m-k and thermal impedance is 0.98 C/W/in² (3mm thick at 20psi). But these figures don’t tell the whole story. Since ThermaSoft can conform so much better to circuit board components, it achieves better heat transfer than other products.

 

[BillParrish]

I tend to agree, but not having one in hard makes it tough to say for sure, but it certainly looks like the mat is a method of keeping the shape of the pad intact as it slighlty melts/oozes under the heat and pressure of operation.

LOL guess I was too slow .

Good info and supports the idea the mat is there by design. I got a chuckle out of this:

Increased pressure on the material no longer results in deformation. This means the ability of the pad to conform to surface features on a circuit board is severely limited. As one frustrated thermal designer expressed it: “It’s like running into a stone wall.”

I guess if the parts were irregular that would be a feature but for sure in this case all that is needed is to make sure the correct thickness (not too thin) is selected as the parts to be mated with the pad are nicely flat. I think that "Engineer" they quoted had run into a couple of stone walls too many or had a very odd implementaion issue.

Going to be a bit tricky to make sure the pads stay where you put them as you apply the heatsink. Careful.

 

[scrumdiddly]

Yeah I'll go ahead with them as they are. It'll be easy enough to position the pads. Fingers crossed!

 

[scrumdiddly]

OK, just to update you guys, it's working perfectly and my GPU temps (8800gt) have gone from 59 idle / 95+ load to 36 idle and around the mid 40s under load, though it might go higher if I run it for longer. Pretty damn good! Time to overclock the hell out of it.