|Sapphire Radeon HD 4870 Toxic Video Card|
|Reviews - Featured Reviews: Video Cards|
|Written by Olin Coles|
|Monday, 29 September 2008|
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Closer Look: Sapphire 4870 Toxic
The Sapphire Radeon HD 4870 Toxic Edition video card (part number 288-10E85-T01SA) isn't anything like the graphics products we've seen from them in the past. To begin with, it departs from the classic ATI red PCB and instead offers a blue printed circuit board. Additionally, we noted the red double-slot sized cooling solution on the original Radeon HD 4870, and this time around Sapphire sticks with black. There are a few small details that seem to stand out as either interesting or unique, and I'll make sure to discuss each at length. Let's begin with overall looks.
ATI originally designed the Radeon HD 4870 with a balanced blend of value and performance, and Sapphire has re-issues a unique version of the 4870 with an added dose to both. The Toxic Edition Radeon HD 4870 video card improves on ATI's latest and greatest single-chip graphics card by adding much-needed cooling improvements and a collection of small performance tweaks. Featuring the industries first implementation of GDDR5 video frame buffer memory, the overclocked RV770 graphics processor is allowed to breathe fire without the worry of burning up video RAM.
There's no denying that Sapphire has improved the cooling design of the reference Radeon HD 4870. As we learned in past reviews of the Radeon HD 4870, this is one extremely warm-blooded video card. Sapphire offers a large 80mm fan to cool their Toxic Edition video card featuring two ball-bearings for long life. The real added incentive is the Vapor Chamber Technology that Sapphire uses in the Vapor-X (nicknamed) heat-pipe cooling solution design.
All Sapphire graphics cards in the HD 4000 series incorporate the latest ATI Avivo HD Technology for enhanced video display and feature a second generation built in UVD (Unified Video decoder) for the hardware accelerated decoding of Blu-ray and HD DVD content for both VC-1 and H.264 codecs, as well as Mpeg files, considerably reducing CPU loading. The dedicated HDMI adaptor connects through the S-Video port and has 7.1 surround sound support and delivers audio and video output on a single cable for direct connection to an HDMI ready display. Unfortunately, there is no support for the up-and-coming DisplayPort interface.
While I am a huge fan of externally-exhausting VGA coolers such as the one used on the reference Radeon HD 4870, I wasn't at all pleased with the exposed electronics that were inherent of the stock cooling package. On the other hand, I am also less enthusiastic about internally exhausting coolers which heat internal hardware, even if they do protect the components.
The cooling unit on the Sapphire Radeon HD 4870 Toxic video card is held tight to the RV770 GPU with the use of a reinforcing bracket and eight screws. The double-height cooler does a very good job of cooling the 4870, but there is still a tremendous amount of heat that builds up on the PCB. If you're an overclocker, there isn't very much that can be done to help cool the unit from the reverse side of the circuit board, especially since there are no surface-mounted GDDR5 modules on this side of the Toxic Edition Radeon HD 4870.
Sapphire's unique double-size active cooling solution is good, but it's not perfect. The RV770 is capable of starting a wild fire inside your computer case, and because of that I feel there are area's that could be improved to bring the cooling solution closer to 'perfect'. Sapphire may have addressed the righteous concern of a taming a blazing-hot GPU, but the Vapor-X cooling system actually vents out of both ends (front and back) which could become an issue.
The RV770 is overclocked from 625 MHz on Radeon HD 4850 to and astounding 780 MHz for this 4870, and the increase in heat output is directly obvious. At idle, the Sapphire Radeon HD 4870 Toxic Edition recorded a cool 43°C, and under load that number raised to 65°C with an ambient room temperature of 23°C.
In our next section we detail our methodology for testing video cards. Following this we offer a cadre of benchmarks to show where the Sapphire Radeon HD 4870 Toxic stands against the GeForce 9800 GTX+, Radeon HD 4850, GTX 260, and an AMP!'ed GTX 280. We even test the HD 4870 Toxic Edition against a set of 4850's in CrossFireX... so please read on!