One of the chief advantages ATIís Radeon 4870 and 4850 enjoy over competing GPUs from NVIDIA is their 8xAA performance. Both of these ATI cards scale ridiculously well when going from 4xAA to 8xAA; weíve tested this extensively in multiple articles over the past few months and this is an advantage ATI has consistently maintained in all our testing. In our 216-core GeForce GTX 260 article we ran 8xAA benchmarks with multiple games. Take BioShock for instance, in this game the GeForce GTX 260 saw its performance drop 16% at 1920x1200. In Company of Heroes we saw an even greater drop of 23%.
Under the same games the Radeon 4870 saw a performance drop of just 9% and 10% respectively!
As smoothly as the Radeon 4870 handles 8xAA though, there is room for improvement. Weíve seen a couple of cases at 2560x1600 where the card runs out of memory running 8xAA at this res (BioShock, Lost Planet), and with graphically demanding games like Far Cry 2 on the horizon, gamers hoping to push 8xAA with these games may run into problems with the 512MB Radeon 4870 at higher resolutions.
To address this ATI has concocted the Radeon 4870 1GB. With double the amount of graphics memory onboard, the card is designed to handle the most demanding games at the highest resolutions with 4xAA and 8xAA. Letís take a quick look at the performance of the Radeon 4870 1GB at 2560x1600 with 8xAA in those two games we mentioned in the previous paragraph:
Whereas the Radeon 4870 512MB basically runs into a wall at 2560x1600 in the above scenarios, the 1GB board continues to scale well. In Lost Planet the 4870 1GB ran 3 times faster than the 4870 512MB at 2560x1600 while the 1GB card ran 5 times faster in BioShock!
Both 4870 cards run at the same clock speeds, so this is a clear case where the larger frame buffer present on the 1GB 4870 card reaps huge performance benefits.
A closer look at the 4870 1GB
Fundamentally the Radeon 4870 1GB shares the same board design and cooling as the Radeon 4870 512MB; physically both cards look identical to one another. And as we just stated, both 4870 cards ship at the same GPU and memory clock speeds.
The only difference is that one 4870 SKU is equipped with 512MB of GDDR5 memory, and the newer 4870 SKU ships with 1GB of RAM. ATI simply uses higher density modules on their 1GB cards.
In terms of pricing, the Radeon 4870 1GB officially retails for $299.99. If you recall this is the exact same price that the Radeon 4870 512MB sold for just three months ago, so ATI isnít charging a ridiculous premium for the added memory. ATI is pitching the card as a competitor to the 216-core GeForce GTX 260, but with the existing 512MB Radeon 4870 performing so well against the enhanced GTX 260, we see it more as a way of future proofing the 4870 line for upcoming games, particularly if youíre a fan of 8xAA gaming.
We did see some performance gains for the 1GB 4870 in areas beyond 8xAA gaming however. Letís get to the benchmarks!