Just in case some of you may be wondering what's the big copper piece, it's a custom heat sink that I created to cool the ATI MR9800.

It takes heat away from the core and the top RAM chips and transfers the heat to the left (where I've used Arctic Silver 5 on the rectangular part of the heatsink over the left CPU heatsink assembly fins). Air from the Dell fan (in the pic) blows over that rectangular part (further cooling the GPU):

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