HEXUS.bang4buck and HEXUS.bang4watt
Putting all the numbers into perspective, let's take a closer look at overall performance and value for money.
In a rough-and-ready assessment of the cards' bang for buck, we've aggregated the frame-rates for all our gaming benchmarks, normalised them1 and taken account of today's pricing.
But there are more provisos than we'd care to shake a stick at. We could have chosen different games, the cards' prices could have been derived from other sources, and pricing tends to fluctuate daily, especially for new-release GPUs such as the Radeon HD 7970.
Consequently, the tables below highlight a metric that should only be used as a yardstick for evaluating comparative performance with price factored in.
Value analysis at 1,920x1,080 |
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|---|---|---|---|---|---|---|---|---|
| Graphics card | Aggregate FPS | Normalised FPS1 | Current price | Bang4buck | Power consumption | Bang4watt2 | ||
| AMD Radeon HD 6990 (4,096MB) | 446.10 | 387.95 | £530 | 0.73 | 362 | 1.07 | ||
| AMD Radeon HD 7970 (3,072MB) | 355.10 | 321.05 | £450 | 0.71 | 252 | 1.27 | ||
| AMD Radeon HD 6970 (2,048MB) | 254.70 | 200.75 | £255 | 0.79 | 237 | 0.85 | ||
| AMD Radeon HD 6950 (2,048MB) | 226.80 | 160.20 | £185 | 0.87 | 194 | 0.83 | ||
| AMD Radeon HD 6870 (1,024MB) | 203.90 | 125.85 | £140 | 0.90 | 187 | 0.67 | ||
| NVIDIA GeForce GTX 590 (3,072MB) | 446.10 | 403.05 | £620 | 0.65 | 407 | 0.99 | ||
| NVIDIA GeForce GTX 580 (1,536MB) | 304.90 | 257.55 | £349 | 0.74 | 285 | 0.90 | ||
| NVIDIA GeForce GTX 570 (1,280MB) | 261.40 | 204.10 | £240 | 0.85 | 245 | 0.70 | ||
| NVIDIA GeForce GTX 560 Ti 448 (1,280MB) | 248.80 | 187.90 | £220 | 0.85 | 271 | 0.69 | ||
| NVIDIA GeForce GTX 560 Ti (1,024MB) | 215.40 | 143.10 | £170 | 0.84 | 225 | 0.64 | ||
Value analysis at 2,560x1,600 |
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|---|---|---|---|---|---|---|---|---|
| Graphics card | Aggregate FPS | Normalised FPS1 | Current price | Bang4buck | Power consumption | Bang4watt2 | ||
| AMD Radeon HD 6990 (4,096MB) | 270.3 | 213.35 | £530 | 0.40 | 362 | 0.59 | ||
| AMD Radeon HD 7970 (3,072MB) | 215.1 | 142.65 | £450 | 0.32 | 252 | 0.57 | ||
| AMD Radeon HD 6970 (2,048MB) | 150.5 | 50.25 | £255 | 0.20 | 237 | 0.21 | ||
| AMD Radeon HD 6950 (2,048MB) | 133.70 | 32.40 | £185 | 0.18 | 194 | 0.17 | ||
| AMD Radeon HD 6870 (1,024MB) | 83.00 | 15.75 | £140 | 0.11 | 187 | 0.08 | ||
| NVIDIA GeForce GTX 590 (3,072MB) | 266.9 | 211.65 | £620 | 0.34 | 407 | 0.52 | ||
| NVIDIA GeForce GTX 580 (1,536MB) | 175.30 | 82.95 | £349 | 0.24 | 285 | 0.29 | ||
| NVIDIA GeForce GTX 570 (1,280MB) | 139.50 | 39.15 | £240 | 0.16 | 245 | 0.15 | ||
| NVIDIA GeForce GTX 560 Ti 448 (1,280MB) | 133.60 | 32.55 | £220 | 0.15 | 271 | 0.12 | ||
| NVIDIA GeForce GTX 560 Ti (1,024MB) | 96.40 | 18.00 | £170 | 0.11 | 225 | 0.08 | ||
1 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.
2 the HEXUS.bang4watt score is a crude measurement of how much normalised performance the GPU provides when evaluated against system-wide 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 Crysis 2.
Summary
Examining the 1080p results first, the Radeon HD 7970's cumulative FPS is 39.4 per cent higher than a Radeon HD 6970's and 16.5 per cent higher than a GTX 580's. The numbers drop when normalising, absolutely, but it's clear this is the fastest single-GPU card in the world. Add in the relative power efficiency and it also scores the best in the Bang4watt metric. That said, the high-ish launch price pushes the Bang4buck to the lower end of the table.
Look at the same results at 2,560x1,600 and the situation isn't all that different. Here it's cumulatively 42.9 per cent and 22.7 per cent quicker, respectively, and the lead increases as the tests become wholly GPU-bound.
The bang4buck graph, which is ordered by performance at 2,560x1,600, spells out an obvious truth. Radeon HD 7970's very solid performance is compromised by a high-ish street price. Drop it down to £400 and it should be near the top at both resolutions.
