gpu cooling block
 

when doing a gpu block is there enough heat to justify direct die or just a regular u over the core (which seems to be common) or would it be better to attempt to do the die and dual exhaust with fins too?

Depends if it's a 'classic' PGA or BGA package (current NVidia cards) or FC-PGA like the ATI 9700 or the Geforce FX.
Then again, the FX has a heat spreader (looks like it), the ATI has a bare core a la AMD.
I'd say, direct cooling on a heat spreader or a PGA package is more efficient than on a FC-PGA core.
About the heat released, current GPUs dont release much heat, and 'maze' GPU blocks we're accustomed to are quite enough.
The FX seems to produce loads of heat (in its ultra flavour), but probably not more than a small CPU.
So is direct-die worth the hassle with a GPU, even if it's more efficient ? I don't think so. Most GFX cards are limited by their RAM interface anyway, so pushing the GPU itslef further brings little to no improvement. And cooling down the RAM has been proven inefficient to OC it.