Sapphire Radeon HD 7790 DUAL-X OC 1GB
Sapphire Technology has released three Radeon HD 7790 models so far. One of them has 2 GB of memory and the other two, 1 GB. We’ve picked up the faster of the 1GB versions which is called Sapphire Radeon HD 7790 DUAL-X OC.
Sapphire’s packaging seems to be the most aggressive with pictures of a warlike girl with a rifle on both sides of the box.
Sapphire offers the best accessories. Besides power cables, adapters, a software CD and documentation, there is an HDMI cable in the box.
A sticker with Sapphire logo is included into the box, too. The card is manufactured in China and costs $130. Its warranty lasts 3 years.
The Sapphire card is cute and small, just like an entry-level product should look, in our opinion. Its face side is covered by a sculpted plastic casing with two fans:
The Sapphire Radeon HD 7790 DUAL-X OC measures 216x101x37 mm (without the mounting bracket). It has a standard selection of video outputs:
Its CrossFireX and power connectors are standard, too:
The PCB follows the reference design in terms of component layout and power system configuration. The empty right part of the PCB seems to have been added to match the cooler, which is longer.
Like on every other card in this review, the power system is managed by a NCP81022 controller:
The GPU of the Sapphire card has a protective frame, so there’s lower risk of damaging it while installing or uninstalling the cooler.
The GPU is pre-overclocked to 1075 MHz in 3D applications. It has the highest ASIC quality in this review:
The memory chips are the same as we’ve seen on the other cards:
There’s a total of 1 GB of memory, which is pre-overclocked to 6400 MHz.
Sapphire’s DUAL-X cooler is quite interesting. It consists of an aluminum base with copper core two identical heatsinks are soldered to.
The heatsinks are pierced with 8mm heat pipes that go out of the cooler’s base. The aluminum plate additionally contacts with the memory chips via thermal pads. There’s a small aluminum heatsink on the power transistors.
The whole arrangement is cooled by two 75mm FirstD fans.
Their speed is PWM-regulated in a range of 1100 to 4400 RPM. When regulated automatically, the fans reached the highest speed in this test session – 2860 RPM. However, the DUAL-X isn’t the best cooler in terms of GPU temperature, which was 67°C.
Auto fan mode
Maximum fan speed
At the maximum speed of the fans the temperature was a mere 6°C lower, which is quite a modest result compared to the leaders of this review.
On the other hand, the Sapphire Radeon HD 7790 DUAL-X OC reached the highest GPU frequency during our overclocking experiments. We managed to increase it by 185 MHz.
The memory wasn’t that good, yet reached 6840 MHz.
The overclocked card had a GPU temperature of 70°C and its fans were rotating at 3000 RPM.
It looks like the Sapphire can hardly beat the others in terms of noiselessness, but we’ll check out its noise level in the next section anyway.