Nvidia GeForce GTX 550 Ti review
Unlike the surprisingly large HD 6790, the 550 Ti is a fairly compact card. It still takes up two expansion slots in your case, but is 223mm rather than 262mm long and only needs a single six-pin PCI Express power connector. It draws just 116W under load, compared to the HD 6790's 150W. On the rear are two DVI connectors and a mini-HDMI, so you'll need the appropriate lead, or an adaptor, to connect it to an HDMI display - PNY's version of the GTX 550 Ti (£116 from www.lambda-tek.com/componentshop) has an adaptor in the box.
Nvidia groups its stream processors into clusters, which it calls Streaming Multiprocessors. The GTX 550 Ti has four clusters of 48 stream processors, giving a total of 192 - the much more expensive GTX 560 Ti has eight clusters, for 384 stream processors in total.
This means that, despite its fast 900MHz clock speed and 1GB of GDDR5 memory, it's no powerhouse. The GTX 550 Ti lagged behind the similarly-priced AMD Radeon HD 6790 in all our tests. In Crysis at 1,680x1,050 with High detail and 4x anti-aliasing, it could only manage 35.6fps compared to 41.8fps, and when we raised the resolution to 1,920x1,080 our frame rate dropped to a barely-smooth 31.2fps, compared to 37.2fps for the AMD card. In our DirectX 11 Stalker test Nvidia's card came out with a below-par 28.3fps compared to the Radeon HD 6790's smoother 33.8fps.
The GTX 550 Ti was easy to overclock with MSI's free Afterburner tool. We pushed up the clock speed to 998MHz and the memory to 1,996MHz, which gave us a 2-3fps boost in all our tests. This still wasn't enough to catch up with AMD's card, though.
While Nvidia's enthusiast 560 Ti is strong competition for AMD's Radeon HD 6950, the GTX 550 Ti can't compete with AMD's latest mid-range cards. The Radeon HD 6790 and HD 6850 remain our favourite graphics cards for gamers on a medium-sized budget.