AMD last week announced the official launch of its flagship graphics card, the Radeon HD 7990 (code named Malta).
The 7990 comprises of two Tahiti GPUs running in dual GPU mode, sort of like CrossFire but just internally by a PLX Technology PEX 8747 switch. This is also what the GTX 690 uses to connect its two GK104 GPUs.
Tahiti’ was the codename of the GPU in the Radeon HD 7970, and since there are two of them inside the 7990, other resources naturally double up. So we’ve got a card here with 6GB of GDDR3 memory in total, split between both GPUs.
With a price tag of $999, it has to compete with Nvidia’s GTX 690 and GTX Titan. It does its job pretty well, mostly meeting or beating the GTX 690 in game-related benchmarks; the 690 in turn beats the GTX Titan pretty soundly.
There are two areas where the GTX 690 outmaneuvers the 7990 coil whine and frame pacing.
The 7990’s circuitry faces some degree of vibration due to fluctuating loads, which emits an audible noise. Of course, the amount of noise you’d actually hear would vary from situation to situation, but it is something to keep in mind. The suggested fix has been to enable V-Sync to lock the FPS at your monitor’s refresh rate, which eliminates a lot of the load variation. The cooling system on the card is reportedly pretty quiet, though.
The other area, frame pacing (or metering), requires a bit of background. Simply put, after a game generates a frame to display and sends it to the GPU, it must go through a buffer. Because of the buffer, frames that go in at a certain rate don’t come out consistently, and thus end-users experience stuttering while playing. This is more of a problem in multi-GPU setups, since there’s more coordination taking place between both GPUs to render the scene.
Nvidia has implemented various frame pacing technologies in its drivers that help keep the frame-flow smooth. AMD hadn’t realised that this was an issue till very recently, hence in some of the games the actual visible frame rate is far lower and less consistent than what the graphics card is capable of pushing.
This is a driver issue and not a problem with the 7990, and AMD’s said they’ll have a proper fix ready by late summer, but it’s a point worth noting.
AMD’s also including 8 games with each 7990 as a part of its Never Settle bundle, but I’m not sure if this offer stands in India, so please do check the boxes if this is important to you (other AMD cards have this offer too in other countries, but again, I’m not sure about India).