Got one of these yesterday. At stock, it's pretty nice and quiet, idle temps were just over 40C, but under load, temps were almost reaching 80C. I removed the heatsink to have a look (actually, that's a lie. I took off the heatsink to see if the Accelero Twin Turbo would fit. It doesn't Stupid DVI connectors and their being-in-the-way) and the finish on the base is absolutely terrible. I took out an old shop cloth and polishing compound and quickly went over the copper baseplate. I also ran over to Mysterybyte and picked up some OCZ Freeze thermal compound. Here are the results:

Idle: 38C
Load: 61C

It shaved just under 20C off my load temperature, and gets pretty damn close to "Vapor-X" performance without even using a different heatsink. Load temps were recorded by running FurMark for half an hour. Ambient temp was about 20C in all cases. I'm posting this here for anyone who also has one of these cards and is experiencing such high temperatures. Not sure if the card I got had an unlucky bad quality HSF or if it was just installed poorly by the factory. Wish I could get that Accelero Twin Turbo on there Maybe a project for later.

Love the card so far. Cheers!

Everyone who bought a stock 5000 series card has high temps

Not really, the fan is at 33%

I meant high temps as generally speaking anything that you will burn your fingers on is too hot! I'm sure the card really doesn't care if it's 86C, which is what mine runs at as well under uberload.

Load temps are a bit high, but it's nice and cool at idle.