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The card’s 16 memory chips are all installed on the face side of the PCB and make up a 1024MB bank with 512-bit access. This sample of GeForce GTX 285 uses GDDR3 chips from Hynix (H5RS5223CFR-N3C) with a capacity of 512Mb (16Mb x 32). These are the fastest chips in the series. They are rated for a voltage of 2.05V and a clock rate of 1300 (2600) MHz. The reference GeForce GTX 285 has a memory frequency of 1242 (2484) MHz, but EVGA squeezed everything out of the chips and lifted the memory frequency up to 1323 (2646) MHz. The resulting memory bandwidth is increased from 158.9GBps to 169.3GBps, which is a record-breaking value for a single-chip graphics card. Considering the simplified wiring and very high default frequency, there is little room for further overclocking.

The GPU is marked as G200-350-B3, being different from cores installed on the GeForce GTX 295 (G200-400-B3) and on the GeForce GTX 260 Core 216 (G200-103-B2). The GPU-Z tool still doesn’t have the revision number of the G200b chip right, reporting B1 for all of them and not telling you the die size and the amount of transistors. Therefore we can remind you that the G200b is 470 sq. mm large and incorporates 1.4 billion transistors.

Our sample of the GPU was manufactured on the 47th week of the last year, i.e. between November 16 and 22. The reference GeForce GTX 285 has GPU clock rates of 648/1476MHz, but EVGA’s card belongs to the SSC series and its main domain frequency is increased to 702MHz while its shader and texture-mapping section is clocked at 1584MHz. The numbers are high for a 1.4-billion-transistor chip even considering the 55nm tech process. We don’t think it can be overclocked more unless you use some extreme overclocking methods. We will check this out shortly, though. The GPU works in its full possible configuration: 240 shader processors, 80 texture processors and 32 raster back-ends.

Despite its terrific complexity, the G200 does not incorporate display connectors which are implemented as an individual NVIO chip you can find near the DVI connectors. There is a bonding pad for a DisplayPort translator above it. We have never seen a GeForce GTX 200 card with such a chip installed, although it would be more appropriate on a modern graphics card than the set of analog video outputs provided by the mini-DIN connector. There is a light pipe above the latter – its end is in the card’s mounting bracket. At the other end of the light pipe there are two LEDs, red and green, which will report any problems with power supply.

Triple SLI technology can hardly be interesting after the release of the GeForce GTX 295. There is no point in building a bulky subsystem out of three cards when you can assemble a more compact and higher-performing system of two cards. However, the GeForce GTX 285 supports Triple-SLI with its two MIO connectors. 

Like 55nm modifications of GeForce GTX 260, the GeForce GTX 285 is equipped with a new reference cooler which is somewhat simplified in comparison with the GeForce GTX 280 cooler. The simplification mostly concerns the heatsink that has become smaller. Besides, the heat pipe that used to cool the load-bearing elements of the voltage regulator is missing now.

It is this section of the cooling system that has been simplified the most, actually. There are even no contact spots with a thermal interface now, and the power transistors are only cooled by the airflow from the fan that comes through the wide slits in the base. The only exceptions are the two inductance coils of the memory voltage regulator. The memory and NVIO chips contact with the cooler’s base through fabric pads soaked in white thermal grease whereas the GPU chip gives its heat away through a layer of dark-gray dense thermal grease to the copper sole that is connected to the heatsink with heat pipes.

The cooler is equipped with a 5.76W blower typical of Nvidia’s products. Its noise characteristics are quite comfortable. At least its motor doesn’t produce the annoying rattling sound like the coolers of the Radeon HD 4870 and HD 4870 X2.

The overall concept of the GeForce GTX 285 design is obvious enough. The engineers have tried to reduce the manufacturing cost of the card. However, the PCB and cooler are designed cleverly from a technical point of view, making this card eligible to the title of the best single-chip graphics card available. We will see if this claim is true in our gaming tests.

 
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