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Getting to know the GeForce 6800 GS
Let's talk swiftly about the graphics core of the the GeForce 6800 GS.
We have to take a best guess here but the the GPU (graphics processor unit) itself is build upon a 0.11 Micron Process technology. Transistor talk then, the 6800 has a lot of transistors not as much as the new 7800 series have but still, it's impressive. There are 222 Million transistors. Imagine all that on a 40mm x 40mm FlipChip GPU running 425 MHz. Amazing. Since we are on the topic of the graphics core, inside it there are precisely five vertex units active. The number of pixel pipelines are identical to the 6800 model, there are twelve.
$ffffffffff ---------------------------------------------------
$ffffffffff Display adapter information
$ffffffffff ---------------------------------------------------
$0000000000 Description : NVIDIA GeForce 6800 GS
$0000000001 Vendor ID : 10de (NVIDIA)
$0000000002 Device ID : 00c0
$0000000003 Location : bus 5, device 0, function 0
$0000000004 Bus type : PCIE
$000000000f PCIE link width : 16x supported, 16x selected
$ffffffffff ---------------------------------------------------
$ffffffffff NVIDIA specific display adapter information
$ffffffffff ---------------------------------------------------
$0100000000 Graphics core : NV42 revision A1 (12x1,5vp)
$0100000001 Hardwired ID : 00c0 (ROM strapped to 00c0)
$0100000002 Memory bus : 0-bit
$0100000003 Memory type : DDR (RAM configuration 07)
$0100000004 Memory amount : 262144KB
$0100000005 Core clock : 12.483MHz
$0100000006 Memory clock : 526.500MHz (1053.000MHz effecti...
$0100000007 Reference clock : 27.000MHz
Above is a BIOS dump from the graphics card taken with RivaTuner, the software which you can observe needs an update when you look at the discrepancies. Let me enlighten briefly what happens in the pixel pipeline for you to understand its importance. Each pixel that is rendered on your screen goes through a pipe where it'll receive its complex color/effect etc. Each time that pixel is altered it'll pass through the pixel pipeline, one pass is one clock cycle. You can imagine going from 8 towards 12 pipes can bring you a nice performance increase. The Series 7 7800 GT(X) actually has 24 of them. They are scalable, each pipe is available at any time in sets of 4, which we call quads.
Specs GeForce 6600 GeForce 6600 GT GeForce 6800 GeForce 6800 GS GeForce 6800 GT GeForce 6800 Ultra GeForce 7800 GT GeForce 7800 GTX Codename NV43 NV43 NV42 NV42 NV40GT NV40U G70 G70 Transistors ? ? 222 million 302 million 302 million Process, GPU maker 110nm 110nm 130nm 110nm 130nm 110nm 110nm Core clock 300 MHz 500 MHz Up to 400 MHz 425 350MHz 400MHz 400 MHz 430 MHz Memory 128MB DDR1 128MB GDDR3 128MB DDR1 128/256MB gDDR3 256MB GDDR3 Memory bus 128-bit 256-bit Memory clock Up to manufacturer 2x500 MHz 2 x 325MHz 2x
500MHz2 x 500MHz 2 x 600MHz 2 x 500MHz 2 x 600MHz PCB P212 P212 P2?? P210 P210 - Pipelines 8 8 12 16 16 20 24 FP operations FP16, FP32 DirectX DirectX 9.0c Pixel shaders Pixel Shaders 3.0 Vertex shaders Vertex Shaders 3.0 OpenGL 1.5+ (2.0) 2.0 Availability Now
| What is a shader ? |
| What do we need to render a three dimensional object; 2D on your monitor? We start off by building some sort of structure that has a surface, that surface is being built from triangles and why triangles? They are quick to calculate. How's each triangle being processed? Each triangle has to be transformed according to its relative position and orientation to the viewer. Each of the three vertices the triangle is made up of is transformed to its proper view space position. The next step is to light the triangle by taking the transformed vertices and applying a lighting calculation for every light defined in the scene. At last the triangle needs to be projected to the screen in order to rasterize it. During rasterization the triangle will be shaded and textured. |
