artic silver isn't a kind of glue. Its just a highly thermally conductive paste that you put between a chip and a heatsink. It doesn't bond with either so it won't be sticky enough to hold the heatsink to the chip by itself, especially considering the video chip is usually on the other side of video cards. You'll need to fasten the heatsink to the chip by some other way if you decide to use artic silver, or any other thermal grease that isn't an epoxy for that matter. Most video cards already come pre-installed with heatsinks which are plugged into the card via 2 holes, so you might be able to use those 2 holes somehow.