here is my 2cents. Ive been through 3 HD5970.. and I have EK, Dangerden, Koolance block. Not to mention I had (3) Defective HD5970.. there are some Q/C controll issues with them (ATI HD5970 )and as far as the Blocks.. I found issues with Koolance, and EK block. I know all the haters out there Dont like Dangerden Block. and in my experience is the best out there!