ATI Mobility Radeon HD 4830
The AMD ATI Mobility Radeon HD 4830 is a slower clocked Mobility HD 4860 and based on the 40nm RV740 core. Therefore, it is similar to the desktop HD 4700 series. Because of the 40nm production process, the power consumption should be similar to the HD 4670 (according to rumors).
Instead of GDDR5 memory of the HD 4860, the 4830 can be only equipped with slow DDR3 or faster GDDR3. Therefore, the 128 Bit memory bus becomes a bottle neck and the performance is clearly degraded.
The gaming performance of the ATI Mobility Radeon HD4830 is sufficient for demanding games of 2009 in medium - high details. Our gaming benchmarks (see below) showed that a high preset in Crysis or NFS Shift resulted in barely playable framerates around 25 fps. Less demanding games, are playable in high resolution and detail settings.
The Mobility HD 4830 is based on the RV740 chip and features 640 stream processors (128 5-dimensional shader cores). These cores do the graphic work of the shader- and pixel pipelines of older GPUs. The stream processors are also called ALUs and are grouped in five-way VLIW units. Each of the five instructions of a VLIW bundle has to be independent from the others and therefore the performance depends on the optimization of the driver.
The Mobility Radeon HD 4830 includes the Avivo HD called video technology including an onboard soundchip for 7.1 sound output over HDMI or DisplayPort and the 2nd generation UVD (Unified Video Decoder). This UVD 2 supports full bitstream decoding of H.264/MPEG-4 AVC and VC-1 streams. In addition to this, it also supports dual video stream decoding and Picture-in Picture mode which makes the UVD full BD-Live compliant. Simplified, the Avivo HD technology handles all video tasks and enables the GPU to decode HD videos.
The HD4830 was replaced by the Mobility Radeon HD 5830, which features a higher shader count (800) and DirectX 11 capable shaders. Therefore, the gaming performance of the 5830 is better, but also the power consumption should be higher (same 40nm process, although more mature).
Compared to the desktop cards, the Mobility Radeon is similar to the ATI Radeon HD 4730. Still, the desktop 4730 offers a noticeable higher performance due to GDDR5 usage and higher clock speeds.
|Mobility Radeon HD 4800 Series|
|Pipelines||640 - unified|
|Core Speed *||550 MHz|
|Memory Speed *||700 MHz|
|Memory Bus Width||128 Bit|
|Memory Type||GDDR3, DDR3|
|DirectX||DirectX 10.1, Shader 4.1|
|Features||Powerplay, CrossFireX support,|
|Date of Announcement||03.03.2009|
|Information||512 - 768 GFlops Computing Power|
|Link to Manufacturer Page||http://ati.amd.com/products/mobilityrade...|