PCB Design

The Radeon X1950 Pro uses a specially developed PCB with a unique design that differs greatly from the PCB design used earlier in the R580-based products. Before the announcement of the Radeon X1950 Pro, the new PCB debuted on the market in the new version of Radeon X1900 GT with a reduced core frequency but an increased memory clock rate relative to the original.

The new PCB has the same dimensions as the old one, but the differences are remarkable, particularly in the right part of the card where the power circuitry is located. As opposed to the Radeon X1900 GT, the Radeon X1950 Pro’s power circuit is digitally controlled and is simplified to the utmost. It incorporates fewer elements, so there is quite a lot of free space in this part of the PCB. Using less transistors and a thinner tech process, the RV570 should boast considerably low power consumption – we’ll check out later on how exactly low it is. The additional power connector has moved from the top right corner down to the middle of the card, near its edge. This may turn to be inconvenient as you are plugging the power cable into an installed Radeon X1950 Pro. Some elements of the power circuit are installed on the reverse side of the PCB, but there are few of them there, too. The power circuit is governed by a Volterra VT1165MF controller.

In its main part, the PCB resembles the Radeon X1900 GT, but only at first sight. There are indeed no fewer differences there than in the right part with the GPU and memory voltage regulators. The memory chips are located at the same spots, but are turned around by 90 degrees. They are not screened as on the previous PCB design. The new PCB must not have been intended for memory frequencies higher than 1.4GHz. In the left top corner you can see two CrossFire connectors. They are not taller than the MIO connectors on Nvidia’s cards, but are wider and have more contacts.

The VIVO-supporting Rage Theater chip still resides in its place. It may not be very useful nowadays but there’s no harm from it, either. It can be viewed as a nice and free bonus Nvidia’s recent cards lack. The Radeon X1950 Pro has a traditional configuration of main connectors: two DVI-I and one S-Video/VIVO. The reference cooler occupies just one slot, and the card’s mounting bracket has an appropriate height.

The new graphics processor from ATI has a rather small die area. It is about 230 sq. mm. Compare this to the R580’s 350 sq. mm and to the G71’s 196 sq. mm. The RV570 still has quite a lot of transistors after all.

The die has a mirror-like surface. The marking tells that we are dealing with a sample of the RV570 chip manufactured on the 34th week of the current year, i.e. at the end of August. The die package is equipped with a metal frame that protects it from damage during installation. A distinguishing feature of the RV570 is that there are very few miniature components on the GPU package: 13 as compared with the R580’s 90.

There are eight chips of GDDR3 memory (Samsung K4J55323QG-BC14) on board, 256Mb each (8Mx32). This yields a total of 256MB of graphics memory. The chips are rated to work at 700 (1400) MHz, but they are clocked at 690 (1380) MHz on this graphics card. One BC14 chip has a max current drain of 935mA and works at 1.8V voltage, so it is easy to calculate that the memory subsystem of the Radeon X1950 Pro card has a peak consumption of only 13.5W.