Radeon HD range. The 7770 is priced at $169 and claims to be the world's first reference GPU that comes factory clocked to 1GHz. Meanwhile, the 7750 comes in at $109 and boasts a low enough wattage (75W, versus 100W for the 7770) that it doesn't require its own power connector. Both cards pack 1GB RAM and run on AMD's Cape Verde architecture, which makes them slightly different to the Tahiti-powered 7900 series, although they do inherit key top-end features like ZeroCore Power, PowerTune and Eyefinity 2.0.
Reviewers have mixed opinions, as befits a healthy blogosphere, but the low-power 7750 generally comes off slightly better, especially for those looking to build a budget or HTPC rig. AnandTech likes the power-to-performance ratio of both cards, but dislikes the price-to-performance of the 7770, noting that the older 6850 still offers more in this respect -- at least for gamers. HotHardware concludes that AMD might have "technically" priced both cards "just right," considering how they stack up against NVIDIA's GeForce GTX560 and 550, but in practice those NVIDIA cards deliver a lot more punch for just a few extra dollars. Feel free to glean further details for yourself via the PR and review links below.