Removing the Heat Spreader (IHS)
Next, we should improve the contact between the core and the cooling system. The graphics chip on 5900XT cards (and on many other GeForce FX cards) is covered with a special lid that serves as a heat-spreader and also protects the core against physical damage. It would be all right, but this solution creates two more layers between the core and the cooling system, worsening the heat-transfer. Instead of the simple “core – thermal paste – cooler” scheme, we have a sandwich like “core – thermal paste – lid – thermal paste - cooler”. That’s not the most efficient way to cool the GPU down.
The cure is simple: remove the IHS. To do this, you need a paper-knife or any other knife with a flat and sharp blade. The procedure is similar to the removal of the frame from RADEONs.
Choose a corner (I prefer the bottom left one) and carefully push the knife under the heat-spreader. It’s handier to position the knife diagonally at that.
Then move the blade deeper, so that it was between the heat-spreader and the chip.
Then take the knife out. Put it in again, but with the tip now, so that the knife was perpendicular to the slit. Don’t push it too hard and far, as this may damage the unpackaged elements on the chip.
Move the blade to a side, releasing the chip from the IHS.
After you reach the second corner, you may probably take the knife out. In our case, the heat-spreader has lifted up so you could catch it with your fingers.