ASUS EAH3850 TOP: Design and Specifications
The ASUS EAH3850 TOP is a precise copy of the reference card from AMD only differing from it with the stickers on the cooler and fan.
The wiring of the power circuit is alike to that of the Radeon HD 3870 but there are almost no discrepancies in terms of the components employed. It is the same two-phase circuit with uP6201AQ and uP6101BSA chips responsible for power supply of the GPU and memory, respectively. Here, the external power supply connector is justifiable since the GPU and memory clock rates of the EAX3850 TOP are considerably higher than those of the reference card.
Like the reference Radeon HD 3850, the ASUS EAH3850 TOP is equipped with GDDR3 memory (Samsung K4J55323QI-BJ11) with a rated frequency of 900 (1800) MHz, but the chips are actually clocked at 950 (1900) which leaves almost no hope for further overclocking. Anyway, the memory bandwidth gain over the reference card is an impressive 7.7GB/s for a total memory bandwidth of 60.8GB/s. That’s far above 44.8GB/s of the Nvidia GeForce 8800 GT 256MB. The 256Mb chips provide a total of 256 megabytes of graphics memory.
The GPU of the EAH3850 TOP is pre-overclocked by the manufacturer from 670MHz to 730MHz. Coupled with the increased memory frequency, this is a promise of a higher performance growth than you can get from the EAH3870 TOP that virtually comes with only one, GPU, frequency pre-overclocked. The GPU configuration is alike to the senior model: 64 universal shader blocks with 5 ALUs in each. 4 large texture processors, and 4 rasterization processors. In fact, the card offers 320 streamed processors, 16 TMUs, and 16 ROPs.
The ASUS EAH3850 TOP can be used in a CrossFireX system together with one, two or three such cards. It offers the same connectors as the senior model: two dual-link DVI-I ports with support for resolutions up to 2560x1600 pixels, and a 7-pin connector for analog video output. Of course, the card supports, by means of an adapter, HDMI 1.1 and the audio-over-HDMI feature.
The card comes with the reference Radeon HD 3850 cooler which is somewhat more complex than the cooler of the Radeon HD 3870 because it called for more advanced cooling technologies to keep cooling performance high while remaining within compact dimensions.
There is a groove in the aluminum base a heat pipes lies in. It takes heat off the copper piece that has contact with the GPU die and distributes the heat uniformly in the heatsink consisting of aluminum plates. The air flow from the blower goes through the heatsink, makes a turn at an angle to the mounting bracket driven along channels in the plastic casing, and is thrown off sideways. The memory chips and the load-bearing transistors of the power circuit give their heat directly to the aluminum base through elastic thermal pads.
This is enough to cool the reference card especially as the heatsink has a larger dissipation area than in the notorious cooler of the Nvidia GeForce 8800 GT but will this design be efficient for a pre-overclocked version? You’ll learn in the next section of the review.