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Dismantled, Peeking Beyond The Cooling...

Enough about the looks, time to dig a bit deeper. Let's see what lies beneath the cooling system of the Gainward BLISS 9800 GX2 graphics accelerator. We are taking a look under the hood by pulling of the cooling solution. As you know by removing the cooling system you are voiding the warranty of your graphics card. So, only for those who don't care about the warranty and want to see what's underneath, with proper handling the heatsink can be removed for whatever reasons. Our reason is plain and simple, what engines are powering the GeForce 9800 GX2 and which other components are present. And to find all about that there is just one way and that is to completely strip the cooling solution of the video card. However we don't recommend it, but at the same wanted to share the real stuff that makes the GX2 what it is today.

After removing the screws, the heatsink can be taken off and the full scale PCB sees the light. Now just to recall, the cooling solution is actually fitted between both PCB's so we are actually removed the PCB at each side of the heatsink. The heatsink itself covered almost completely the two PCB's, with the cooling system being a bit heavier than the PCB's. Most electronic components have been invisible from the start on the back side of the PCB which was visible after removing the casing. All main components like the GPU, voltage regulators and memory chips however could only be seen once the cooling solution was taken off. Quite normal these days for any high-end graphics accelerator as cooling has become an important aspect. In this particular case both PCB's did fit on the cooling solution, which cooled down both cards and also made sure to hold the cards together.

The Gainward BLISS 9800 GX2 version is powered by the new G92 series line of graphics processors. The G92 core used is physically the same chip as you will find back on the GeForce 9800 GTX video cards and features the unified shader technology, represented by the stream processors. The NVIDIA G92 chip uses a 65nm manufacturing process for its high performance circuits and has been designed from based upon the very successful G80 though having gone through a die shrink and with a more optimized unified shader logic. The GeForce 9800 GX2 comes with two G92 cores and each working at 600MHz operation speed, actually a bit lower clocked than the GeForce 9800 GTX which is set at 675MHz. Though as having two G92's running in SLI mode, it delivers much higher gaming performance and experience. With the introduction of the G92 core we see that a new era being kicked off which is all about the unified shader technology and how to optimize this logic further.

	GeForce 8800 Ultra	GeForce 9800 GX2
Core Speed	612MHz	600MHz
Memory Speed	2160MHz	2000MHz
Stream Processors	128	256
Shader Speed	1500MHz	1500MHz
Memory Size	768MB GDDR3	1024MB GDDR3
Memory Interface	384-bit	512-bit

To incorporate this within the GeForce 9800 series we see that NVIDIA has come up with the stream processors which can be used in a unified way as either vertex or pixel shader. That means that these are no longer fixed to just being a vertex or pixel shader, but their function changes according to the processing needs. With an unified GPU architecture some bottleneck between pixel, shader and geometric processing is reduced to a great extend. These stream processors have their own speed setting, which is called the shader clock. For the GeForce 9800 GX2 card the shader clock is set at 1500MHz, but scalable up to 1800MHz according to the specifications. The Gainward BLISS 9800 GX2 edition comes with sixteen memory chips in total which are all located on the front side of each board. That means that each PCB has their own G92 processing chip with corresponding 512MB frame buffer.

The memory chips are placed strategically around the G92 core. Each of these memory chips are cooled by the inner heatsink which makes contact with the top of each memory chip and as such taking care of cooling these in a very adequate manner. By cooling the memory chips as well, it does provide extra protection towards the lifetime of the chips in general. The ram chips are placed four by four and give a total of 512MB memory per board, and that means 1GB for the graphics card as a whole. The GeForce 9800 GX2 video card features Samsung branded GDDR3 memory which is running at 2000MHz speed. These Samsung GDDR3 chips come marked as 1.0ns access time and are therefore rated at 2000MHz frequency and normal operating at 1.9V. This means that these are run at default clock speed and that means generally that some more performance can be gained by simple way of overclocking.

There is a new chip on the card that NVIDIA developed that acts as a physical PCI Express bus splitter, namely the BR04 bridge switch. In order to connect the second GPU to the rest of the system, a PCI Express bridge is used. The markings BR04 reveal that this chip is the nForce 200 bridge used on the nForce 780i motherboard designs for example. This BR04 bridge chip will take care of the connection between both G92 graphics chips, and also handle the PCI Express signals to make sure the GeForce 9800 GX2 requires only one single PCI Express interface. In contrast to the current dual GPU solution from AMD, meaning the Radeon HD 3870 X2 graphics card we see that NVIDIA is supporting the PCI Express 2.0 specifications and that the overall interconnection is fully compliant with this standard. Well that's about it on the insights of the Gainward BLISS 9800 GX2 graphics card. So we will just reassemble it again, applying some new thermal compound and stick it into our test system.