Sapphire HD 7970 6GB Toxic Edition Reviewccokeman - July 16, 2012
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All I can say is that Sapphire hit this one out of the park, to use a baseball analogy. The HD 7970 6GB Toxic Edition delivers best in class performance against other HD 7900 series cards in part by way of the incredible clock speeds both stock and overclocked. Clock speeds of greater than 1200MHz on the core and 1600MHz on the memory are not going to be possible without having a good base to start with. Sapphire has the baseline covered with a custom 12 layer PCB and its Lethal power suite design. This design uses an eight phase power delivery system for the GPU core voltage with a separate phase for the VRAM and controller for a good stable flow of current to the card. Additionally, double sided Black Diamond chokes and DirectFET technology are used to reduce the operating temperatures for the power circuits by upwards of 40%.
Cooling the HD 7970 6GB Toxic edition is an all new Vapor-X cooling solution that keeps the 28nm core and the 6GB of onboard memory cool to deliver rock solid performance. Using a four heat pipe design with the cooling solution keeps the card cool at both stock and overclocked settings. When the fan is pushed to 90% the GPU core stays at 54 °C during my overclocked testing; that is overclocked and over volted. At 90% the noise generated by the fans is audible but not so much so that it borders on annoying. The fans used are 90mm in size and use an aerofoil design to improve airflow and manage noise characteristics. Fans slowing down and dying have killed many a video card without the owner even knowing what went south until it is to late. To combat this the fans used on the Toxic Edition have fans that use a dust reeling design to improve fan longevity. It's a small thing but well worth mentioning.
The only downside to a cooling solution like the one employed on the Toxic Edition is that it can increase the temperatures of the components installed in the chassis. Manage the airflow in your case and that concern goes away with the heat. A nice touch on this card is the use of a series of LEDs on top of the PCB near the mounting bracket that give a visual indicator of the PCB temperature. Green, yellow, and red LEDs work like a stoplight to let you know all is well and when the card can be ramped up. In testing the Toxic Edition HD 7970, I never saw anything other than a series of green and at most a single yellow when really cranking on the voltage showing the indicator does what it is supposed to do.
When it came to overclocking this card I was pleased to see the clock speeds of 1235MHz on the core and 1735MHz on the 6GB of memory. The only other HD 7970 I have tested to reach this level was a factory overclocked and water cooled HD 7970; driving the cooling significantly lower while needing more current than I had to use on the Toxic Edition HD 7970. Sapphire added to the feature set on the Toxic Edition with several means of overclocking the card. The first option is the Lethal Boost button that boosts the clock speeds on the core up to a dynamically boosted 1200MHz and 1600MHz on the 6GB of memory. To get this boost in performance all that is required is to push the button and reboot; it could not be simpler. Manually tweaking the card is still an option with Sapphire's own free to download TriXX utility, which was used to generate my overclocked results. Each GPU is going to have variations in clock speed margins and voltage tolerances and in this case the core did better with a lower applied voltage (1174mv) in comparison (1250 to 1300mv) to some others I have worked with. Ultimately this helps keep the card cool under load as the cooling solution is nowhere near overworked.
The performance results with the HD 7970 6GB Toxic Edition are easily well above those of even factory overclocked cards I have tested including the comparison cards in this review. At times this puts it right into the realm of the performance envelope delivered by the NVIDIA GTX 680, especially at a resolution of 5760x1080, which really is where this card is designed to shine with the 6GB frame buffer. There was not a single game tested that the HD 7970 6GB Toxic Edition could not handle at "Eyefinity" resolutions with a good bit of the eye candy turned on. Just what the gamer with three screens wants. The bundle of accessories included with the card will allow three screen gaming without having to purchase a Mini DP to DVI active adapter as it part of the bundle. Just one less impediment to getting started.
The Sapphire HD 7970 6GB Toxic Edition is a limited edition card built upon the AMD HD 7970 GHz Edition specification, but pushed to the upper end of the spectrum; both in price (estimated at $680) and in performance delivered. I have to say I was impressed with what Sapphire has brought to the table with this card. After looking at many of its past special edition cards, this one lives up to the heritage of the Atomic and Toxic series and extends the performance legacy cultivated by Sapphire.
- High clock speeds
- Overclocking Margin
- Custom PCB
- Lethal Boost
- Excellent cooling
- One button overclocking
- "Flex" Feature set