Testing methodology
GPU comparisons |
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|---|---|---|---|---|---|---|---|
| Graphics card | Approx. pricing |
GPU clock (MHz) |
Stream processors |
Shader clock (MHz) |
Memory clock (MHz) |
Memory bus (bits) |
Graphics driver |
| Sapphire Radeon HD 6870 1,024MB | £130 | 900 | 1,120 | 900 | 4,200 | 256 | Catalyst 11.12 |
| Sapphire Radeon HD 6850 1,024MB | £110 | 775 | 960 | 775 | 4,000 | 256 | Catalyst 11.12 |
| Sapphire Radeon HD 6790 1,024MB | £100 | 840 | 800 | 840 | 4,200 | 128 | Catalyst 11.12 |
| HIS Radeon HD 6770 1,024MB | £75 | 850 | 800 | 850 | 4,800 | 128 | Catalyst 11.12 |
| PowerColor Radeon HD 7770 1,024MB | £125 | 1,000 | 640 | 1,000 | 4,500 | 128 | Catalyst 12.1 |
| AMD Radeon HD 7750 1,024MB | £90 | 800 | 512 | 800 | 4,500 | 128 | Catalyst 12.1 |
| Gigabyte GeForce GTX 550 Ti OC 1,024MB | £100 | 970 | 192 | 1,940 | 4,200 | 192 | ForceWare 295.51 |
| ASUS GeForce GTX 560 Direct Cu 1,024MB | £130 | 810 | 336 | 1,420 | 4,004 | 256 | ForceWare 295.51 |
Mainstream Test bench |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CPU | Intel Core i5 2500K (3.3GHz, 6MB L3 cache, quad-core, LGA1155) | |||||||||||
| Motherboard | Intel DP67BG | |||||||||||
| Memory | 8GB Corsair Vengeance (9-9-9-24-2T @ 1,600MHz) | |||||||||||
| Power Supply | Corsair AX750 | |||||||||||
| Monitor | Dell 30in 3007WFP | |||||||||||
| Disk drive(s) | Crucial RealSSD C300 (256GB) | |||||||||||
| Chassis | Corsair Graphite Series 600T | |||||||||||
| Operating system | Windows 7 SP1, 64-bit | |||||||||||
Benchmarks |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3DMark 11 | Performance and Extreme presets | |||||||||||
| Aliens vs. Predator | DX11, 1,280x720 and 1,920x1,080 resolutions, 2xAA, 8xAF, medium quality. | |||||||||||
| Batman: Arkham City | DX11, 1,280x720 and 1,920x1,080 resolutions, 4xAA, high quality | |||||||||||
| Battlefield 3 | DX11, 1,280x720 and 1,920x1,080 resolutions, 0xMSAA, 16xAF, high quality | |||||||||||
| Crysis 2 | DX11, 1,280x720 and 1,920x1,080 and resolutions, 0xAA, 16xAF, high quality | |||||||||||
| Just Cause 2 | DX10, 1,280x720 and 1,920x1,080 resolutions, 4xAA, 16xAF, medium quality | |||||||||||
| Total War: Shogun 2 | DX11, 1,280x720 and 1,920x1,080 resolutions, 4xAA, 8xAF, high quality. | |||||||||||
| Power consumption | To emulate real-world usage scenarios, we record mains power draw both when idle and whilst playing Shogun 2 | |||||||||||
| Temperature | To emulate real-world usage scenarios, we record GPU core temperature both when idle and whilst playing Shogun 2 | |||||||||||
| Noise | A PCE-318 noise level meter is placed at front of a Corsair 600T chassis with side panel on. | |||||||||||
| Overclocking | Pushing the graphics card as far as it will go, we increase speeds and re-run the Aliens vs. Predator benchmark | |||||||||||
| HEXUS bang4buck | A custom metric used to evaluate comparative performance with price factored in | |||||||||||
Notes
We've tested eight graphics cards from the grounds-up for this test! The entire stack of Radeons are actually run on the press driver for the Radeon HD 7770/50 cards - 8.932.2-120206a-133032E-ATI - and it's identified as Catalyst 12.1 for the Cape Verde GPUs and Catalyst 11.12 for the remainder.
The line-up is interesting, too, as the Radeon HD 7770's predicted £125 pricing puts it up against some very stiff competition. Search around the web and you can find the Radeon HD 6870 for £130 (or less) and the HD 6850 for £110. Though they're destined to be made end-of-line in about a month or so, giving way to HD 7000-series love, they need to be included to give you, the readers, the most-complete buying advice possible at this moment in time.
Radeon HD 6770 is, for all intents and purposes, a rebadged HD 5770 that was released in October 2009. It's worth including because it shows what advances, if any, AMD has made to the x770 family over two generations and 28 months. Do remember that HD 5770 was around £125 on launch, as well.
NVIDIA's mainstream stack is thinner in comparison. GeForce GTX 550 Ti starts at around £85 and runs up to £120 or so, depending upon model. The next rung up is the vastly more powerful GeForce GTX 560, now available for £130, and it can be thought of as a well-overclocked GeForce GTX 460 1GB.
As far as has been possible, we've used retail cards instead of AMD/NVIDIA press samples. The only factory-overclocked card is the Gigabyte GTX 550 Ti, and we feel comfortable in adding this because its £100 street price is close to the HD 7750's.
Most readers tend to look at the pure performance numbers. The comparisons to look out for are Radeon HD 7770 vs. Radeon HD 6870 vs. GeForce GTX 560, and Radeon HD 7750 vs. GeForce GTX 550 Ti.
