ATI Radeon HD 4500/4300: Family Portrait
The ATI Radeon HD 4500/4300 series is based on the 55nm RV710 core. This core is simpler than the RV730 in many respects as we will describe below after we compare the new chip’s specs with those of Nvidia’s products.
The RV710 is the simplest and smallest entry-level GPU in the table. It incorporates a mere 242 million transistors and measures 73 square mm (40% smaller than the 55nm G96 core from Nvidia). However, the new GPU boasts impressive computing potential. It has as many as 80 ALUs, which is 2.5 times as much as in the full-featured G96. Each five ALUs are grouped into one execution module and each eight modules are combined into a SIMD array serviced by four texture processors. Thus, the RV710 incorporates two SIMD arrays and eight texture processors, which is impressive in comparison with the GeForce 9400 GT as well as with the more expensive GeForce 9500 GT, the market opponent to the Radeon HD 4670. Now let’s check out the architectural features of the new core.
As opposed to the RV770/730, the RV710 does not have separate texture and vertex caches. Its rasterization subsystem has been simplified relative to the RV770/730. The raster back-ends are twice slower at blending operations whereas the hardware MSAA resolve is limited to 4x as opposed to 8x of the senior GPU models. This simplification is reasonable because it helped reduce the amount of transistors in the RV710 without cutting down the overall functionality of the core. After all, this GPU is not meant for playing at high resolutions with high-level antialiasing.
The memory subsystem is represented by one memory controller servicing two 32-bit channels. Thus, the total width of the external memory bus is 64 bits. The use of rather fast DDR3 memory helps achieve the same memory bandwidth as that of the GeForce 9400 GT on a simpler PCB because there is no need to wire a 128-bit memory bus. The simpler PCB lowers the manufacturing cost of the product. So, we won’t be surprised to see the developer cut the price of the Radeon HD 4550 to make it even more appealing in comparison with Nvidia’s products from the same category.
The multimedia subsection of the core has been left intact. It incorporates the industry-leading UVD2 video-processor that offers full support for decoding of both H.264 and VC-1 formats. Nvidia’s solutions are still deficient in this respect.
The new GPU also features an integrated audio core which can output eight-channel audio over HDMI, also in the high-definition formats Dolby TrueHD and DTS-HD. ATI is still superior here because even Nvidia’s flagship solutions do not offer such advanced audio capabilities, being limited to simple translation of S/PDIF audio into HDMI.
Overall, the Radeon HD 4550 looks like a bargain for its recommended price of $45-55, especially in comparison with its opponents that are not only more expensive but also have weaker technical capabilities, particularly in terms of HD video decoding and HDMI audio support. The new card should find its place in advanced HTPCs that are not intended for intensive gaming. The Radeon HD 4350 comes at a recommended price of only $39, which makes it an appealing buy, too. However, it has slow memory and can hardly be much faster than integrated graphics solutions in 3D games.