Review: AMD Radeon HD 7770

Following on from our look at AMD’s latest úber-powerful graphics cards from their HD 7900 series, we now cast a glance down towards the other end of the performance spectrum at the HD 7700 series.

Aimed towards HTPC (Home Theatre PC) users and gamers on a budget, the HD 7770 and HD 7750 represent the bottom end of AMD’s Southern Islands family of graphics cards (the HD 7970 and HD 7950 are at the top end, with the HD 7870 and HD 7850 occupying the middle).

Despite being the cheapest cards from the new range, this segment of the GPU market is the most competitive – far more “budget” video cards are sold each year compared to “enthusiast” cards – so consumers expect top bang-for-buck as well as the latest features.

Priced at $239 NZD, the HD 7770 is an approximate replacement for last season’s HD 6850. Packing 640 stream processing units running at 1000MHz and 1GB of GDDR5 memory running at 4.5GHz on a 128bit bus it doesn’t look as powerful as its predecessor on paper, however it is built on AMD’s new 28nm GCN (Graphics Core Next) architecture which clock-for-clock should perform a bit better than the older technology.

A big drawcard for all these Southern Islands cards is their GPGPU capabilities, such as hardware-accelerated video encoding (similar to Intel’s Quick Sync technology). Unfortunately at time of writing AMD had not yet enabled this feature in its drivers and there was no software available to test it, so it is something we will have to follow up on in future.

So what are these cards best suited for, in practical terms? In our gaming test suite the HD 7770 scored an average of almost 40 FPS (frames per second) across a range of titles at high quality settings compared to less than 33 FPS from the 7750, both of which are actually respectable figures for “budget” cards. After turning the graphics settings down in Battlefield 3, I found the HD 7770 ran ‘medium’ settings at a comfortable 50 FPS, whilst the HD 7750 had to use ‘low’ mode for the same performance.

As for HTPC use – both are similar in terms of video processing capabilities (see our HD 7900 series reviews for more info) so you would really need to weigh up what factors are more important to you out of power, heat, size and noise. The HD 7770 is a physically much longer and wider card (could be a problem in ultra-small cases), plus it requires a 6pin power connector where the HD 7750 runs solely on motherboard power.

On the flip side the larger cooler exhausts a lot of heat externally and can run quite quietly, as opposed to the HD 7750 which just pushes all waste heat around the inside of your case and has a small, high-RPM fan that can get annoyingly noisy under any sort of sustained load.

If you intend to do any sort of gaming then the HD 7770 is definitely the way to go, otherwise if you are really stretched for budget then the HD 7750 would still be a decent upgrade from something like an “onboard” GPU, and both of them would be fine for HTPC use, bearing in mind the small caveats mentioned above.

Benchmark/Stat	Details	AMD Radeon HD HD 7970	AMD Radeon HD HD 7950	AMD Radeon HD HD 7770	AMD Radeon HD HD 7750	Nvidia GTX 580	AMD Radeon HD 6850
3DMark 11 (score)	Performance (1280 x 720)	7857	6759	3467	2682	6689	3696
Battlefield 3 (FPS)	High	88.2	73.6	39.3	29.3	684	38.9
S.T.A.L.K.E.R. Call of Pripyat (FPS)	Ultra, DX11, 4xAA, HBAO high, Tesselation enabled	102.9	86.4	42.3	32.1	88.2	43.5
Unigine Heaven 2.5 (FPS)	Default	67.3	58.7	30.4	24.6	55.7	31.6
Trackmania Nations Forever (FPS)	Very high, 4xAA	84.5	83.5	62.3	56.9	117.0	69.6
Anno 2070 (FPS)	Very high	51.7	42.4	25.1	21.3	42.9	26.2
Average FPS		78.9	68.9	39.9	32.8	74.4	42.0
RRP incl GST		$899	$699	$239	$179	$799	$249
Dollars per FPS (lower = better)		$11.39	$10.14	$5.99	$5.45	$10.73	$5.93