I installed a swiftech mcw50 block on my 6800ultra and vantec iceberg vga ram sinks. My ram sinks don't appear to be sticking all too well. I've been fiddling around with my vid card and knocked a few off just by touching them. Is there a way to fasten them or when I start running my vid card the heat will help them stick? I don't want these guys to fall off and potentially ruin my card.