HEXUS.bang4buck, temps and overclocking
HEXUS.bang4buck
In a rough-and-ready assessment of the cards' bang per buck, we've aggregated the 1,920x1,200 frame-rates for the four games, normalised them* and taken account of listed the cards' prices
But, even so, there are more provisos than we'd care to shake a stick at. We could have chosen three different games, the cards' prices could have been derived from other sources and pricing tends to fluctuate daily.Consequently, the table and graph 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 | XFX GeForce GTX 260 XXX 896MiB | NVIDIA GeForce GTX 260 896MiB | BFG GeForce GTX 280 1024MiB | ZOTAC GeForce 9800 GX2 1024MiB | BFG GeForce 9800 GTX | Sapphire Radeon HD 4870 | Sapphire Radeon HD 4850 | Sapphire Radeon HD 3870 X2 1024MiB |
|---|---|---|---|---|---|---|---|---|
| Actual aggregate marks at 1,920x1,200 | 276.99 | 253.89 | 309.02 | 306.75 | 192.13 | 225.86 | 180.99 | 202.02 |
| Aggregate marks, normalised*, at 1,920x1,200 | 201.52 | 184.99 | 224.86 | 228.33 | 134.17 | 162.71 |
126.51 |
151.29 |
| Current pricing, including VAT | £283 |
£249 |
£422 |
£299 | £179 |
£179 |
£125 |
£229 |
| HEXUS.bang4buck score at 1,920x1,200 | 0.712 | 0.743 |
0.533 |
0.764 |
0.75 |
0.909 |
1.01 |
0.661 |
| Acceptable frame rate (av. 60fps) at 1,920x1,200 | No (Crysis, LP) | No (Crysis, LP) | No (Crysis, LP) | No (Crysis, LP) | No (ET, Crysis, LP) | No (Crysis, LP) | No (ET, Crysis, LP) | No (Crysis, LP) |
* 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 bang4buck score of 30 marks. The minimum allowable frame rate is 20fps but that scores zero.
As an example, should a card score 120fps we treat it as 90fps as only half the frame rate above 60fps is counted for the bang4buck - this is the formula: (120-((120-60)/2)). Similarly, should it score 30fps, we count it as only 15fps: (30+((30-60)/2)).
The reasoning behind such calculation lies with playable frame rates.
Should card A score 110fps in a benchmark and card B 160, then card B would otherwise receive an extra 50 marks in our bang4buck assessment, even though both cards produce perfectly playable frame rates and anything above 60fps is a bonus and not a necessity for most.
Similarly, without our adjustments, the aggregated bang4buck total for two very different cards would be identical if, in a further benchmark, card A scored a smooth 70fps and card B an unplayable 20fps. Both would win marks totally 180, yet the games-playing experience would be vastly different.
A more realistic (and useful) assessment would say that card A is better because it ran smoothly in both games - and that view would be accurately reflected in our adjusted aggregation, where card A would receive 150 marks (85+65) and card B 100 (100+0).
In effect, we're including a desired average frame rate, in this case 60, and penalising lower performance while giving frame rates higher than 60fps only half as much credit as those up to 60fps. If this doesn't make sense or you have issue with it, please hit the HEXUS community.
Here's the HEXUS.bang4buck graph at 1,920x1,200.
The graph divides the normalised score by the price.
The XFX GeForce GTX 260 XXX is a far better value-for-money proposition than the GeForce GTX 280: it benchmarks reasonably close to the 280 yet costs considerably less. That's why its 0.71HBFB (HEXUS.bang4buck) score is way higher than the 0.53HBFB attributed to the BFG GeForce GTX 280.
However, the same argument can be put forward for the £179 Radeon HD 4870 512MiB card. It's no XXX-beater, of course, but performance is good at 1,920x1,200. The substantial £100+ saving means that its HEXUS.bang4buck looks even better.
We suppose that line of thinking can be extended right down to the Radeon HD 4850, but we'd rather not sacrifice playable frame-rates for additional cost savings over and above the HD 4870's. There comes a time when sticky frame-rates compromise the aggressive pricing, and that stage arrives at somewhere between HD 4870 and 4850 when evaluated at 1,920x1,200.
Temperature musings
We perform our testing in an open test bed, with a 120mm fan simulating case airflow.
| Graphics cards | XFX GeForce GTX 260 XXX 896MiB | NVIDIA GeForce GTX 260 896MiB | BFG GeForce GTX 280 1024MiB | ZOTAC GeForce 9800 GX2 1024MiB | BFG GeForce 9800 GTX | Sapphire Radeon HD 4870 | Sapphire Radeon HD 4850 | Sapphire Radeon HD 3870 X2 1024MiB |
|---|---|---|---|---|---|---|---|---|
| Ambient temperature | 24°C | N/A | 21.5°C | 22°C | 21.5°C | 25°C | 21°C | 19°C |
| Idle temperature | 48°C | N/A | 47°C | 60°C | 52°C | 71°C | 71°C | 56°C |
| Load temperature | 72°C | N/A | 74°C | 80°C | 67°C | 83°C | 81°C | 80°C |
| Ambient-to-load delta | 48°C | N/A | 52.5°C | 58°C | 45.5°C | 58°C | 60°C | 61°C |
It's a cool-running GPU when looked at in comparison to the Radeons, and it's quieter too.
NVIDIA's done an excellent job with the cooler and fan; the combination doesn't suffer from the poor-ish speed regulation on the HD 4850/70s.
Overclocking
640/1,363/2,300MHz, the native frequencies of the card, are pretty
ambitious. We managed to raise them further, up to 650/1,404/2,400MHz
with a 30-minute bout of overclocking. End result? The
1,920x1,200 4xAA 16xAF benchmark of 77.7fps in ET:QW was pushed out to
79.7fps - or 10 per cent slower than a GeForce GTX 280.We don't imagine that users will attain much-higher frequencies without resorting to some other form of cooling. XFX is already pushing the air-cooled possibilities to the limit, especially if, as we presume, stability is far more important to the company than sheer on-paper specifications.
