HEXUS.bang4buck and bang4watt
Putting all the numbers into perspective, let's take a closer look at overall performance.
In a rough-and-ready assessment of the cards' bang for buck, we've aggregated the 1,920x1,080 frame-rates for four games, normalised them* and taken account of the cards' prices.
But there are more provisos than we'd care to shake a stick at. We could have chosen four different games, the cards' prices could have been derived from other sources - we tend to stick with listings from two of the UK's largest retailers - and pricing tends to fluctuate daily.
Consequently, the table below highlight a metric that should only be used as a yardstick for evaluating comparative performance with price factored in. Other architectural benefits are not covered, obviously.
| Graphics cards | ASUS GeForce GTX 480 1,536MB | ASUS GeForce GTX 470 1,280MB | ASUS GeForce GTX 465 1,024MB | Gigabyte GeForce GTX 460 SOC 1,024MB | EVGA GeForce GTX 460 1,024MB | EVGA GeForce GTX 460 768MB | Sapphire Radeon HD 5870 1,024MB | HIS Radeon HD 5850 1,024MB | ASUS Radeon HD 6870 1,024MB | HIS Radeon HD 6870 1,024MB | Sapphire Radeon HD 6850 1,024MB | HIS Radeon HD 5770 1,024MB |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Aggregate FPS (1,920x1,080) |
305.1 |
249.7 |
204.8 |
235 | 197.1 |
185.9 |
244.6 | 208.5 |
223.8 |
222.2 |
194.3 | 144.9 |
| Normalised* FPS (1,920x1,080) |
260.35 |
201.35 |
151.2 |
184.1 | 145.05 |
131.05 |
214.1 | 170.15 |
186.3 |
183 |
150.85 |
93.45 |
| Current pricing | £350 | £200 | £170 | £175 | £155 | £135 | £275 | £210 | £190 | £195 | £150 | £110 |
| bang4buck (1,920x1,080) |
0.744 | 1.007 | 0.889 | 1.052 | 0.936 | 0.971 | 0.779 | 0.810 | 0.981 | 0.938 | 1.006 | 0.850 |
| GPU power consumption** | 244 | 204 | 195 | 169 | 169 | 130 | 139 | 117 | 132 | 126 | 97 | 90 |
| bang4watt*** (1,920x1,080) |
1.067 | 0.987 | 0.775 |
1.089 | 0.858 |
1.008 | 1.54 | 1.454 |
1.411 |
1.452 |
1.555 |
1.038 |
* the normalisation refers to taking playable frame rate into account. Should a card benchmark at over 60 frames per second in any one game, the extra fps count as half. Similarly, should a card benchmark lower, say at 40fps, we deduct half the difference from its average frame rate and the desired 60fps, giving it a HEXUS.bang4buck score of 30 marks. The minimum allowable frame rate is 20fps but that scores zero.
** the GPU power consumption is derived from subtracting a flat rate of 100W - indicating system power-draw without a card - from the Call of Duty: MW2 load figure. While this figure isn't solely indicative of power pulled by the GPU, as the CPU also throttles up, it's a better metric than using peak system-draw alone.
*** the HEXUS.bang4watt score is a crude measurement of how much normalised performance the GPU provides when evaluated against GPU power-draw that's shown in the table: the former is divided by the latter. We're using the peak power-draw numbers obtained by running real-world Call of Duty: MW2.
Evaluation
The extra 15MHz frequency over a regular HD 6870 doesn't buy you a whole heap more performance, as clearly demonstrated in the HEXUS.bang4buck. The card's normalised score is a touch lower than a heavily-overclocked GeForce GTX 460 1,024MB's and some way down on a stock GeForce GTX 470. This means that the value proposition - aka HEXUS.bang4buck score - is good rather than great.
Radeons score better in terms of under-load power efficiency, because even the custom-designed Gigabyte GTX 460 cannot match the power-draw exhibited by the HD 6870. We'd give the performance nod to NVIDIA, call features a tie, and hand AMD the energy-efficiency crown.
