Overclocking

Sapphire overclocked its Toxic card from reference 750MHz to 780MHz and the memory by 100MHz from reference 900MHz. The performance scaled well with overclocking, as gaming also reported 4% performance increase.

Only some RV770 graphics chips will run over 850MHz, and we were quite happy with our Sapphire Toxic HD 4870 as we pushed it to 860MHz with no trouble. Memory allowed for additional 150MHz and we ended up at 1150MHz (4600MHz effectively). Hefty memory clock increase resulted in bandwidth jumping to 147.2GB/s, which is 27GB/s higher than reference 115GB/s. During our quite long gaming tests we’ve noticed artifacts only once, but we’d still not recommend such high clocks.



In 3DMark 06 test, the card scored 17048 after overclocking, whereas the non-overclocked card scored 16600 points.

After we did our overclocking, Left 4 Dead reported up to 10% better results. At 2560x1560 and filters on, Sapphire Toxic HD 4870 scored 55,06fps, whereas our overclocking resulted in 60,66fps.

Temperatures



Toxic Vapor-X cooling does a great job and during operation runs up to 28 °C cooler than reference. Idle temperatures sit around 46°C but workload scenarios result in up to 59°C, which is still better than reference 87°C.

Toxic cooling runs quiet in idle operation, but noise levels get close to reference ones during operation.


Power Consumption



Sapphire’s Toxic HD 4870 consumes only a few Watts more than reference, so the consumption increase is so slight that it’s negligible. 


Conclusion

Sapphire Toxic Radeon HD 4870 card features non-reference dual-slot cooling and higher core and memory clocks. The cooling based on Vapor Chamber technology ensures that the 780MHz core stays up to 28°C cooler than reference 750MHz core. We’re looking at a 30MHz factory overclock as well as a 100MHz memory overclock up to 1000MHz (4000MHz effectively). Radeon HD 4870 is a great gaming card, and Sapphire surely brings it to the next level.

Compared to the reference 512MB card, Sapphire’s card brings 3-5% better results and you can increase the up to 10% if you do some manual overclocking. Toxic HD 4870 features 512MB of GDDR5 and it will be enough unless you like them high resolutions and filters on. In that case, you’d be better off buying a 1GB memory card, or even wait for Sapphire’s HD 4870 2GB version.

Higher clocks and Toxic Vapor-X cooling do however come at a price and you’ll have to pay around €20 more compared to the reference card’s price. If you want a fast HD 4870 with some powerful cooling, then this card just might strike your chord.