|Sapphire Toxic 512MB Radeon HD3870 Graphics Card
After some benchmarking and a bit of 3D gaming at the stock settings, the Catalyst Control Center's Overdrive tab was used in order to overclock the card's GPU and memory. While it does come overclocked from the factory, I was hopeful that a bit more horsepower could be squeezed out of the Toxic Radeon HD3870.
The overclocking capabilities of the Overdrive utility are pretty limited, and it is generally rather easy to max out the GPU clock using it. HD3870 GPUs generally hit the ceiling at around 860MHz unless the BIOS is modified, so while I did not think that it would reach the 885MHz indicated as the maximum allowable speed on the Overdrive tab, I did think it would go much faster than 800MHz. I started out with two broad jumps in GPU speed, going from 800MHz to 820MHz and then 840MHz. Then smaller steps were taken to try out 845MHz all the way up to 885MHz. Stress testing at each stage showed that the temperatures were still good, and that the card was still stable. Much to my surprise the card climbed right past 860MHz and was perfectly stable at 885MHz!
With the GPU clock returned to 800MHz, I then overclocked the memory. The Overdrive tab indicates that you might be able to get up to 1387MHz, which seems unlikely considering the stock speed is 1152MHz. I gave it a 50MHz bump right off the bat and everything was good. I then bumped it up in 5MHz increments and arrived at 1227MHz rather quickly. To be honest, I was hesitant to go higher as it is not as easy to monitor the health of the memory as it is on the GPU. 1227MHz is quite a high memory speed, effectively 2.454GHz GDDR4!
With a moderate overclock (with the GPU at 855MHz and the memory at 1197MHz) a few benchmarks were executed. The total score in 3DMark06 rose 311 Marks over stock, and the average framerate of a few 3D games rose by 1-3 fps. With the highest overclock (with the GPU at 885MHz and the memory at 1227MHz) the tests were run again. The 3DMark total score was now 521 Marks higher than stock, and the same games were putting out 3-5 fps more. Nothing tremendous, and as we will see in the testing section the card doesn't suffer in the performance department at stock speeds anyway. But if you like to squeeze every last drop of juice out of your components, those few extra frames per second may be worth going after.
A system with the following components was used to test the Sapphire Toxic 512MB Radeon HD3870 graphics card:
» Intel Core 2 Duo E6850 3.0GHz Dual Core processor
» OCZ Technology Vendetta CPU cooler
» ASUS P5KC P35 ATX motherboard
» Kingston HyperX PC-9200 2GB DDR2 dual channel memory running at 1066MHz, 5-5-5-15
» Maxtor MaxLine III 250GB SATA 3Gbps hard drive
» Tuniq Miniplant 950W power supply
All tests were conducted in Windows Vista Home Premium with all updates current as of early May 2008. In lieu of the driver's provided with the card, version 8.471.1 of the ATI Catalyst software (which includes a hotfix for compatibility with 3DMark Vantage) was used.
For comparison purposes the following two cards were used in this review:
» 512MB Sapphire Toxic Overclocked Radeon HD3870
» 512MB ASUS EAH3870 TOP Overclocked Radeon HD3870
The images below show the Sapphire Toxic 512MB Radeon HD3870 graphics card side-by-side with the ASUS EAH3870 TOP. What can be seen is that while the cards have the same depth and width, the Sapphire card's single slot cooler makes it look much smaller when placed next to the two slot cooler found on the ASUS model. While all of the hot air is exhausted back into the case with Sapphire's design, their Vapor-X cooler is touted to provide more effective cooling than the bigger, more traditional design.
The chart shown below compares the basic features and specifications of these two overclocked Radeon HD3870 cards as compared to a 'generic' model. The Sapphire card is just 25MHz faster than a generic HD3870 in terms of GPU clock, while the ASUS card 76MHz faster. But when we look at the memory clock data we see that the Sapphire card is faster than the ASUS card by 9Mhz.
The core clock and fillrates on the ASUS card are higher, while the memory clock and bandwidth is higher on the Sapphire card. Just based on this preliminary data, my assumption is that the ASUS card might hold the edge. The testing portion of this review will address that, though.