AMD's newest 40nm based Radeon HD 4770 was a great success, maybe more successful than many people expected. Together with the limited availability due to yield problems there were very few Radeon HD 4770 boards available on the market and those sold quite quickly. To counter this shortage, AMD has created the Radeon HD 4730 which is based on the RV770 which powers the Radeon HD 4800 series, yet it's heavily reduced in features. Just as an example the number of shaders has been lowered to 640 and the memory interface has just been cut down to 128-bit, but GDDR5 memory chips are still used which effectively gives it the same bandwidth as an 256-bit based Radeon HD 4830 card. - techPowerUp

Sapphire Radeon HD 4730 512MB Style Board Review

Now due to the design of the memory controller the number of raster operating units have been halved as well. And also please note the considerably higher core clock of these Radeon HD 4730 compared to other cards like the Radeon HD 4850. Sapphire is one of two partners who are making the Radeon HD 4730 at this time, PowerColor is the second. And we are told by Sapphire the Radeon HD 4730 chipsets have to be ordered specifically from AMD. This means that partners are not just using their excess Radeon HD 4830 chips on such cards. It could still mean that AMD ships their excess GPU's as Radeon HD 4730's.

Sapphire uses their lite retail package for their Radeon HD 4730 card. This allows them to be more cost effective and doesn't give you a huge package with a lot of useless stuff in it. The graphics card looks very similar to Sapphire's Radeon HD 4830 even though a different PCB seems to be used. So with the cooler the card requires two slots in your system. You may combine up to four Radeon HD 4730 boards in CrossFire for increased performance or higher image quality settings. Though there is no official statement whether you can mix the Radeon HD 4730's with other RV770 based cards, and all our attempts were fruitless.

The idea of releasing a lower mid-range card based on the RV770 chipset makes a lot of sense. It gives AMD an opportunity to sell off their chips that didn't qualify to be used on the higher end boards, and helps fill the void in the market that is caused by the Radeon HD 4770 shortage and makes for a potential successor to the Radeon HD 4830 seeing less availability. Unfortunately the implementation of the board is less than optimal. In order to make up for the reduced shader count and memory bandwidth the core clock has been increased significantly. In order to achieve such clocks with current GPU bins the voltage had to be increased.

Higher voltage means higher power consumption which severely limits the card's ability to perform. This increased power gives more heat that has to be dissipated via the cooler, resulting in a more noisy experience. Actually Sapphire's Radeon HD 4730 performance itself is quite sufficient to run all of the todays games at modest resolutions. This makes the board an excellent deal at its current price point of $79. However given the high power draw and fan noise, the GeForce 9600 GT or Radeon HD 4770 are better choices at this time when you are looking for the best bang for the buck.