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PCB Design and Features

The AMD Radeon R9 295X2 uses liquid cooling, which makes it quite unusual in appearance. There are two pipes sticking out of the otherwise normal-looking dual-processor card. A radiator with fan is fastened to the ends of those pipes.

You may identify the cooler as one of the numerous Asetek clones. We’ll discuss its design later on. Right now, let’s have a closer look at the graphics card proper.

The dual-processor AMD Radeon R9 295X2 measures 305x100x39 millimeters, being larger than the regular Radeon R9 290X/290 but somewhat smaller than its dual-processor predecessor Radeon HD 7990. The face side of the card is covered by the cooler casing with a bright red fan in the center.

The reverse side of the card is covered with a metal plate that only has small square openings opposite the GPUs and tantalum capacitors.

The edges of the cooler casing are perforated to let out the air from the fan. You can see the pipes of the liquid cooling system here.

There are four mini-DisplayPorts (version 1.2) and one DVI connector on the card’s mounting bracket. Half of it is a vent grid.

There is no CrossFireX connector, just like on the Radeon R9 290X/290. Graphics cards are now combined into multi-GPU configurations via the PCI Express interface.

The AMD Radeon R9 295X2 is equipped with two 8-pin power connectors, each rated for up to 28 amperes.

AMD even published a special file with recommendations about the power supply the Radeon R9 295X2 needs, naming specific PSU models. The graphics card is specified to consume up to 500 watts. An 850-watt or higher PSU is recommended for it.

The next photo gives you some notion about the card’s design.

So, it consists of a PCB, a slim metal back cover, a heat-spreader with waterblocks and a casing with fan. The casing is secured with screws and can be removed easily. Under it, we can find two waterblocks with pumps on the GPUs, a copper heatsink in between, and a heat-spreading plate.

After removing the waterblocks, we see GPUs with too much thermal grease on them.

We didn’t remove the heat-spreading plate as we wanted to keep the thermal pads in their places. But judging by the photos from the official presentation, each GPU has a 5-phase power system with one additional phase for the graphics memory and PLL each. The power systems are managed by ON Semiconductor controllers and you can see additional tantalum capacitors on the reverse side of the PCB.

The two 28nm Hawaii XT GPUs communicate via a PLX 8747 controller that supports 48 PCIe lanes. They were both manufactured in Taiwan on the 41st week of 2013 (in the first half of October). Each GPU die is 438 sq. mm large and incorporates 6.2 billion transistors.

  

The AMD Radeon R9 295X2 carries two full-featured Hawaii XT GPUs with GCN architecture, each with 2816 unified shader processors, 176 texture-mapping units and 64 raster operators. The peak 3D clock rate of the GPUs is 1018 MHz, which is 18 MHz higher compared to the Radeon R9 290X. Theoretically, the Radeon R9 295X2 may be more than twice as fast as one R9 290X provided that CrossFireX technology shows its best.

In 2D applications the GPU clock rate is dropped to 300 MHz and the voltage is reduced, too. The ASIC Quality of the two GPU chips is 71.8% and 73.3%.

The AMD Radeon R9 295X2 is equipped with 4 gigabytes of graphics memory per each GPU. Like with every other dual-processor card, each GPU uses its dedicated memory bank, so the memory amount should be specified as 2x4GB. The 16 chips of GDDR5 memory surround the GPUs on both sides of the PCB. They are clocked at 5000 MHz in 3D applications. The peak memory bandwidth is 320 GB/s as confirmed by the GPU-Z utility.

The graphics card has one main and one backup BIOS chip. Both chips contain the same BIOS code.

And now let’s check out the cooling system installed on the AMD Radeon R9 295X2.

 
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