Sorry for the late answer,
You need to use the adapter on 79xx and 280x cards with an universal gpu waterblock since the chip is slightly recessed and won't make contact with the waterblock without it.
The Tech Reps from Ek should have told you that. If you check on...
Hi,
Did you use the "EK-VGA Supreme HF HD7970 Cu Adapter" between the chip and block.
Otherwise there is no contact made between block and chip.
link: http://www.ekwb.com/shop/blocks/vga-blocks/universal-vga-blocks/universal-vga-blocks-accessories/ek-vga-supreme-hf-hd7970-cu-adapter.html
S3 virge
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