Sapphire Radeon HD6970 FleX Edition review

Photo of Sapphire Radeon HD6970 FleX Edition

Sapphire’s FleX Edition range of cards have been designed to make it easier to implement AMD’s Eyefinity multi-screen technology. This is without having to resort to using a DisplayPort equipped monitor, or having to buy expensive third-party active dongles. You have to use one of these two options for a standard card, as you can’t use the DVI and HDMI ports both together, concurrently, as both share a clock generator. This was always the Achilles heel of AMD’s original idea. Using a FleX card you can power up to three monitors straight out of the box, or if you do go down the dongle route, you can get to a five-screen setup. The current flagship of the range is the Radeon HD6970 FleX.

Problem solved

Sapphire’s answer to the problem, AMD created, is to give the HDMI port a clock generator of its own. This is all so that it’s not tied to the DVI, simple really, which makes you wonder why AMD never thought of this, in the first place. With two DVI outputs and a single HDMI, you have three-way Eyefinity support without any messing about.

Ports a plenty

The rear I/O plate carries two DVI outputs, which are coloured differently from one another, this is because one is Single Link DVI while the other is Dual Link. The difference is Single Link DVI supports monitors with resolutions up to and including 1,920 by 1,200, while Dual Link can support screens with resolutions up to 2,560 by 1,600. Next to the DVI ports sits the HDMI port, along from this are the two mini DisplayPort 1.2 ports. If you have a DisplayPort enabled screen or screens, then using one or both of these will allow you to set up a four/five screens in Eyefinity.

Turbo boost….of sorts

At the top of the PCB is a tiny, but important two-way switch that lets you switch between either using the HD6970 FleX Edition, at the reference core clock speed of 880MHz, or to run it at a very mildly overclocked speed of 930MHz. The 2GB of GDDR5 memory that the card is equipped with, runs regardless of switch position at the standard 1375MHz (5500MHz effective) clock speed.

Keeping everything cool is a Sapphire designed dual slot Vapor-X, vapour chamber cooler that has a large 88mm fan in the centre. This not only keeps the card cool, but it does so considerably quieter than the AMD’s reference design

Frame scores

The mild overclocking option offered by the cards switch doesn’t do an awful lot to improve the performance of the HD6970 FleX Edition, over the standard card. In the Xtreme (1080p) test, in 3DMark 11, a standard clocked HD6790 gave a score of 1810. The FleX Edition brought in a score of 1843. It’s a similar story when it came to gaming benchmarks. At the same 1080p (1,920 x 1,080) resolution, the standard card gave average frame rate scores in Aliens v Predators of 55fps and 62fps, in DiRT3. The FleX edition gave up frame rates of 63fps and 69fps, in AvP and DiRT3 respectively. Connecting the card up to two monitors to get a 3840 by 1080 resolution, the frame rate for AvP dropped to 31fps, and in DiRT3 to 41fps.

Lots in the box

The HD6970 FleX needs the services of a 6-pin PCI-E and 8-pin PCI-E adaptor, to get it moving along, but don’t worry if you haven’t got any spare. Sapphire has bundled in both a 4-pin Molex to 6-pin PCI-E, along with a 4-pin Molex to 8-pin PCI-E and all the adaptors you need to get going; DVI to VGA, DVI to HDMI, a Mini-DP to DP cable and really usefully a 1.8m HDMI cable.

Company: Sapphire


  • Eyefinity out of the box.
  • Factory overclock isn’t that much faster than standard, but that’s just nitpicking.


The fastest card in Sapphire’s FleX line-up carries on the good work, done by the previous generation. If you want to setup Eyefinity without the tears, it’s the only ball game in town.