I posted this at overclock.net ati/amd forum also..
Figured I would share this with you guys.. I found something yall will find entertaining...
I had a hunch and I was correct. I guess an old dog can get lucky from time to time..
Heres my $20 cooling mod.. I also ordered a 20gram tube of Artic mx-4.
The donor is one burnt up Sapphire hd7870 ghz edition.... The parts as needed, one 4 copper pipe heat sink, the small black memory heat sink, the shroud and fans from the HD7870 ghz edition and the retention frame from the rx480..
I do need to order two replacement fans as one of them on the shroud is bad, so I'll order a pair and have a spare.., I need to order some heat sinks for the other 4 memory chips after I figure out what I want or need, or if I even need them, I think there will be plenty of air on the rear chips..The side chips will have the black heat sink on them, they are the the chips covered by the 4 heatpipes..
I actually thought I'd need to machine some clearance some where but its pretty much a drop on install as far as I can see.. All of the the pictures below of the heatsink on the 480, it is bolted down with the factory retention plate and screws..
its been a complete bolt on.... I was thinking the bolt hole sizes were different but that wasnt the case..
The difficulty of the install has been removing the factory stuff and bolting on the hd7870 heatsink and fan shroud and using the rear rx480 support and bolt it on, like it was meant to be there...
There looks to be plenty of clearance where there needs to be for some heatsinks.. I think the rx480 support frame/fan brace will fit but the rear fan will need to be removed. and the hump of the frame that goes over the 6pin connector... I might need to trim some places here and there on the frame but thats no problem for a retired mold maker...
I havent tested it and wont be able to for a few days as I'll be waiting on fans and possibly heatsinks to arrive..
Heres what pics I've taken so far, i'll likely add some more... That blue on that shroud is ugly and needs to be red..