TweakTown posted a review on the Diamond Radeon HD 4870 XOC Black Edition

The other day we looked at the Smooth Creations Asylum and inside was the new Diamond HD 4870 XOC Black Edition. This isn’t your normal overclocked HD 4870, though; if you have a look at the specifications on the thing, you will quickly discover that the card is packing some mega serious clock speeds.

So what we’ve done is pull the card out of the Smooth Creations rig and install it into our testbed to see how the card performs against some of our other favorites. Since this wasn’t a retail sample, we won’t be looking at the package today. What we will do is have a quick look around the card and then check out the clockspeeds before moving onto the testing phase.

Diamond Radeon HD 4870 XOC Black Edition Review