Page 9 - Power Usage, Overclocking
Our complete test platform with no graphics card uses 129W on idle. With that in mind, the Asus 3870 TOP performed really well in terms of idle power management -- the RV670 advantages can really be seen here. At 157W idle for the complete system power consumption, it's only 30W over no graphics card idle and uses roughly 20W less than the 8800GT in this state. Nice.
The load conditions cannot be measured against no graphics card since the entire system is under load, and as such the CPU which will not limit to only graphics card power consumption. However, these figures are accurate against each other besides the 'None' value as 129W as a place filler -- but much to our surprise, the ATI Radeon HD3870 actually used a little more power than the 8800GT under load. It's still quite a bit lower than the 8800GTS G80 and 8800GTS G92, which we are quite thankful for.
Out of the box, Asus already overclocked the ATI Radeon HD 3870's core to 851MHz -- an impressive 76MHz overclock or 10% faster than AMD specifications. We were not able to push it up any further -- a MHz higher and it's insta-crash. Some users report around 10MHz or so overclocking though, but in this area we can only say... good luck, and have fun.
It's clocked high out of the box anyway!
Let's see.. for memory, the Samsung DDR4 chips used by Asus are awesome. AMD specifications requires the memory to run at 1125MHz (Actual clock), but Asus has it at 1140MHz. Now, the most interesting thing is that these sets of memory are rated for 1200MHz -- so they are actually underclocked 60MHz. We were able to hit 1318MHz stably -- which is, really impressive as far as I'm concerned. That's 193MHz over AMD specifications (17.2%), 15.6% over Asus TOP specifications, and 9.8% over Samsung memory specifications. Either way, 2.6GHz effective clock is nothing to joke about!
1. Introduction, Specifications, Bundle
2. AMD 3870 Architecture
3. A Closer Look, Test System
4. Benchmark: FEAR
5. Benchmark: Prey
6. Benchmark: Half Life 2: Lost Coast
7. Benchmark: CS:Source HDR
8. Benchmark: 3DMark06
9. Power Usage, Overclocking
10. Noise Factor and Conclusion