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PCB Design

The Gainward brand has long been a property of Palit Microsystems, so there is no wonder that the described card uses a unique PCB design that has little in common with the reference Radeon HD 4850. The mounting quality is high although some inductance coils are tilted and there are traces of flux where the power transistors of the voltage regulator are soldered in.

The PCB of the Gainward HD 4850 1024MB GS is somewhat shorter than the reference card’s, which is good. It will be easier to install the card into compact system cases. However, it carries a more advanced three-phase GPU power circuit (as opposed to the two-phase regulator of the reference card). The voltage regulator is based on a PWM controller NCP5388 manufactured by ON Semiconductor. This chip is often employed in Palit’s nonstandard designs and is also used in the new reference design for GeForce GTX 260 Core 216.

An Anpec APW7065 based regulator is responsible for the memory chips.

There is one unique feature about the power circuit of the Gainward HD 4850 1024GB GS. It uses only one 8-pin PCI Express 2.0 connector. The card does not start up when you plug in a 6-pin PCIe 1.0 cable into this connector, displaying an appropriate message on the monitor. We don’t know the reason for such an unusual solution but it cannot be high power consumption. The card comes with a simple 6-pin → 8-pin PCIe adapter, so it might as well be equipped with a 6-pin connector.

The memory chips are turned by 90 degrees in comparison with the reference Radeon HD 4850. These are eight Samsung K4J10324QD-HJ1A chips of GDDR3 memory. They have a capacity of 1Mb (32Mb x 32), a voltage of 1.85V, and a rated frequency of 1000 (2000) MHz as denoted by the HJ1A suffix. The card’s memory frequency is 1000 (2000) MHz for a bandwidth of 64GBps, just as with ATI’s reference sample. Despite the noble title Golden Sample, the Gainward card won’t be able to compete with the Radeon HD 4870 with its super-fast GDDR5 memory in this respect. The only advantage over the ordinary Radeon HD 4850 is the double amount of graphics memory: 1 gigabyte as opposed to 512 megabytes. This may come in handy in some games as we will see in our tests.

The card’s RV770 chip was manufactured on the 26th week of 2008, i.e. June 21-29. As usual, there is no useful info we can get from the marking on the die but the GPU-Z program reported the following:

The GPU has a standard configuration with 800 ALUs grouped into 160 superscalar execution modules, 40 TMUs and 16 RBEs. The frequency is increased over the reference card from 625MHz to 700MHz. This is 50MHz less than the frequency of the Radeon HD 4870, but may come in handy in games that are sensitive to the GPU frequency, for example Prince of Persia. Besides, the GPU may be overclocked even more as we will check out soon.

The card has a standard set of interface connectors: two dual-link DVI-I ports, a universal 7-pin analog video output, and two CrossFireX connectors.

 
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