I'm having a fair amount of trouble with my FC XSPC block. I mounted it on my VisionTek 4870 (512MB, ref design), and it died. I had just had a leak that killed my motherboard so I figured it had taken the GPU with it and I ordered a new 4870. This time an XFX 4870 (1GB, ref design again). I tested it to make sure it wasn't DOA and it worked in both my PC and my parents PC. So I go ahead and mount the waterblock. Now it is dead too (dead as in no video, and when booting with a PCI 2400Pro, the GPU isn't detected). I checked on XSPC's website and I did exactly what the tutorial .PDF said to do both times but I managed to somehow kill both cards. I have RMA'd the second GPU, but I'm both hesitant to use the XSPC waterblock and I wan't to use it so I didn't waste my money. Anyone have any idea what I may have done to damage both GPUs, and how I can prevent this with my newest XFX 4870. Thanks.