Minor Gains and a Compromise
At $249, the R9 285 doesn't exactly redefine the landscape with only 4% more performance on average than the card it will be replacing, the R9 280. Even if you discount the big loss in Tomb Raider, which could possibly be driver related, the R9 285 is still just 6% faster than the R9 280. Bringing a 4-6% boost for the same price obviously isn't bad, but we're not sure if the R9 285 was completely necessary either.
Keep in mind again that the Sapphire card we tested was overclocked by 5% so our results are likely inflated by 2-3%, making the margin between the R9 285 and R9 280 even thinner. We couldn't underclock the Sapphire card and this has been an issue since the Radeon 200 series popped up. If anyone knows a workaround please let us know (other than flashing the BIOS, which we couldn't do in time).
On the subject of overclocking, we imagine gamers would benefit more from the R9 280's superior memory subsystem than the R9 285's tweaks. As far as we could tell, Tonga doesn't offer any radical performance enhancements over Tahiti to make it worth investing in a card with a 256-bit wide memory bus over one with a 384-bit bus. It also doesn't really challenge the GTX 760 any more than the R9 280 did.
The R9 285 uses a little more power and costs 4% more than the GTX 760 but is 7% faster, though again that last figure doesn't account for our sample's overclock. If you remove that from the equation, the R9 285 and GTX 760 are even closer in value. That's essentially the same relationship the GTX 760 had with the R9 280, which used more power but delivered a bit more speed for a few extra bucks.
It's unfortunate that the R9 285 doesn't shake things up a little more. If you already own a R9 280, HD 7950 or anything faster, then the R9 285 isn't for you unless you need features such as Mantle API or DX12 support. If you were already eyeing the R9 280 and don't mind a memory downgrade, the R9 285 is a fine choice while it's probably a better pick than the GTX 760 if you want the most frames per dollar.
score
Pros: For the same price as the R9 280, the R9 285 brings a slight performance boost along with some extra features such as support for DirectX 12, the Mantle API, TrueAudio and FreeSync.
Cons: The R9 285's 256-bit memory bus is downgraded from the R9 280's 384-bit bus. Although it has a performance edge on the GTX 760, it costs a little more and uses a little more power.