Asus Radeon HD 7790 DirectCU II OC review

Just like Sapphire’s Best Buy-winning implementation of the new AMD Radeon HD 7790 GPU, the Radeon HD 7790 Dual-X OC, the Asus Radeon HD 7790 DirectCU II OC is intended to plug the gap between lower-end graphics cards such as the Radeon HD 7770 and mid-range cards such as the Radeon HD 7850. The Radeon HD 7990 GPU is a 28nm process that provides 896 stream processors, a 128-bit memory interface and up to 96GB/s of memory bandwidth, although the Asus Radeon HD 7790 DirectCU II OC only provides 60GB/s. For comparison, the Radeon HD 7770 has 640 cores and the Radeon HD 7850 has 1024, so the Radeon HD 7790 really is placed neatly in the middle.

It also has a similar specification, with a GPU clock speed of 1.08MHz and 1GB of GDDR5 memory running at 1.6GHz, both of which are an increase on the reference card’s clock speeds of 1GHz and 1.6GHz respectively. It’s also cooled by two fans, just like the Sapphire version and has one 6-pin PCI-E power connector. One difference between the Sapphire and Asus cards is the maximum memory bandwidth available, with the Asus model providing 60GB/s, which is slightly less than the Sapphire’s 64GB/s.

The Asus Radeon HD 7790 DirectCU II OC’s retail package is less generous than that of the Sapphire Radeon HD 7790 Dual-X OC, as it only contains a DVI-to-VGA adaptor and a CrossFire connector. The Sapphire also provides a HDMI lead and a Molex-to-6-pin power adaptor in addition to those items.

Its 215mm length means it should easily fit in many desktop cases, and it provides two DVI, one HDMI and one DisplayPort output. These outputs, combined with the included DVI-to-VGA adaptor allow a good deal of flexibility when connecting your displays. If you’re lucky enough to have a few spare displays, you can connect up to four of them to the card.

GAME SPEED

In keeping with tradition, our first benchmark test involved Dirt Showdown running at a resolution of 1,920×1,080 with 4x anti-aliasing and quality options set to Ultra. Just like the Sapphire HD 7790, the Asus Radeon HD 7790 DirectCU II OC didn’t disappoint, providing a smooth average frame rate of 57.6fps. This is ever-so-slightly higher than that provided by the Sapphire Radeon HD 7790 Dual-X OC, which returned an average frame rate of 55.3fps. It’s also faster than our reference Radeon HD 7770, which scored 40fps in the same test.

When we dropped the resolution to 1,280,×720 and set the graphical quality options to High, the frame rate leapt up to an average frame rate of 106.6fps. The Sapphire version scored 106fps exactly, which is so close you can regard it as the same result.

Next, we ran our more challenging Crysis 2 benchmark at a resolution of 1,920×1,080 at Ultra quality and saw an average frame rate of 24.4fps. Although this is a pass, it’s still too jerky for smooth, comfortable play. Thankfully, we had only had to lower the quality settings one level to Extreme to see an average frame rate of 37fps. This is much more comfortable, but dropping the quality settings to Very High achieved an even higher frame rate of 43.6fps.

This compares well with the Sapphire Radeon HD 7790 Dual-X OC, which, at a resolution of 1,920×1,080, provided average frame rates of 24.6fps at UItra quality, 36.6fps at Extreme quality and 46.3fps at Very High quality. Again, this is so close as to be read as exactly the same result.

If you don’t mind playing Crysis 2 at a lower resolution of 1,280×720, you’ll experience smooth frame rates at Ultra quality from the start. Under these conditions, we saw an average frame rate of 48.4fps.