The foremost question is performance, and in that sense, the Radeon HD 7990 did very well according to most of the reviews. However, it did little to shine over NVIDIA's GTX 690 and even a couple of 7970 cards in Crossfire mode. Comparing the HD 7990 against the GTX 690, Anandtech found that the 7990 is statistically tied with its rival, and HotHardware agreed, stating that while the 7990 scraped through victory most of the time, there were games like Skyrim and The Witcher 2 where NVIDIA's dual-GPU solution proved to be quicker. The combined forces of the 7970 cards tend to perform better as well; for example, Anandtech found that while running Crysis 3 in high quality, the 7990 benched at 41.2 fps, the GTX 690 at 41.5 fps, while the Crossfire 7970 topped the list at 46 fps. After a real-world test, the crew at Tom's Hardware concluded that game play on the GTX 690 felt smoother too. In almost all instances, however, the 7990 handily beats the single-GPU GTX Titan, outperforming it by as much as 20 fps in some cases.
As we expected, the 7990 is an absolute beast when it comes to power consumption. HotHardware slotted it as the highest of the cards it tested, noting that under load, its power consumption was over 100 watts higher than the GTX 690. In terms of noise level, the 7990's open-air three-fan system turned out to be much quieter than the GTX 690, and it's certainly cooler than two 7970s put together -- Tech Spot discovered that the 7990's temperature never exceeded 72 degrees. However, it's still not exactly silent. Tom's Hardware found that the 7990's power-related vibrations actually created more sound than the whirring fans themselves. Still, others like Hot Hardware say that noise is a "non-issue" with the HD 7990 despite its high power consumption. Overclocking didn't seem to improve its performance that much, with Bit-tech stating that even then, the 7990 couldn't beat the pair of 7970s in Crossfire -- its Unigine score improved just six points to 2177, far from the latter's score of 2442.
In the end, most reviewers couldn't recommend the 7990 over the alternatives. It does come bundled with eight top-shelf gaming titles -- Crysis 3, Battlefield 3 and Bioshock Infinite to name a few -- which makes its hefty price tag easier to swallow, but that wasn't enough to sway the crowd. Tom's Hardware noted that while it's certainly better than its predecessor, it comes up shy of its competition: "The GTX 690 is shorter, set up to exhaust at least some of its waste heat out of your chassis, and significantly more power-friendly... NVIDIA simply sells a better-built dual-GPU graphics card."
Bit-tech similarly concluded that you would be better off either getting two 7970 GPUs running Crossfire if you want better performance, or the GTX 690 if you're short on space. For Anandtech, the GTX Titan remains the one to get despite its lower frame rate because of the consistency and simplicity of strong single-GPU cards over their multi-GPU compadres. Tech Spot agreed with the choice, claiming that the Titan offered better overall frame time performance than the 7990. Seeing as both the GTX 690 and GTX Titan are priced similarly at $1,000, it's ultimately your call on where you want to spend that precious grand.
If you're keen on sussing out the Radeon HD 7990 for yourself before making that choice, check out the benchmarks and full reviews in the links below.
Read -- PC Perspective
Read -- TechSpot
Read -- Anandtech
Read -- Tom's Hardware
Read -- HotHardware
Read -- Bit-tech