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The Technical BlahblahThe GT card tested today will be offered in 128 and possibly 256 MB configurations. I expect you to go for the 256 MB version as that's the trend, however we received the 128 MB model. The GeForce 6600 series product line has 8 Pixel pipelines and 3 Vertex processors that are confirmed to be working 100% with Rivatuner:

$0100000000 Graphics core : NV43 revision A2 (8x1,3vp)

The 6600 series can write four color pixels per clock and has a fragment crossbar. The NV43 does appear to have eight pixel shader/texture units, so its not an "8 x 1" design or a "4 x 1" design. It's more of a hybrid and works quite well. When we look at clock rates something very interesting is happening here. Where the PCI-Express models are have the memory clocked at (2x)500 MHz, the AGP version has been down-clocked a little and is running at (2x)450 MHz, or 900 MHz effectively for NVIDIA's standard reference model.

Galaxy however is doing stuff a little different. This card's core is running at 525 MHz and it's memory at 1.05 GHz at default! Armed with some nice cooling that results in 45 Degrees C idle load and roughly 60 Degrees C at 100% utilization. Very nice. So this AGP version is running a heck of a lot faster compared to the competition.

Overall the performance between AGP and PCI-Express is about the same. One can only speculate about the frequency difference. One possibility is that cheaper memory was need to offset the added cost of the HSI bridge chip (more on that later) that was needed for the AGP version. Whatever the reason, this could mean some very nice potential for overclocking performance, as this product is a little memory bandwidth limited.

Let's have a look at the cards configuration and compare it to NVIDIA's GeForce Series 6 product line:

$ffffffffff Display adapter information
$ffffffffff ---------------------------------------------------
$0000000000 Description : NVIDIA GeForce 6600 GT
$0000000001 Vendor ID : 10de (NVIDIA)
$0000000002 Device ID : 00f1
$0000000003 Location : bus 1, device 0, function 0
$0000000004 Bus type : AGP revision 3.0
$0000000005 AGP status : enabled
$0000000006 AGP rate : 4x 8x supported, 8x selected
$0000000007 AGP SBA : hardwired, enabled
$0000000008 AGP FW : supported, enabled

Among the next pages you'll see a photoshoot of this product. It'll show you a bit more clearly how NVIDIA accomplished making the NV43 (Series 6600), which is a PCI-Express GPU, compatible with AGP 8x. Actually it's quite simple. You all know that NVIDIA was able to make AGP products PCI-Express compatible compatible (ex: the PCX5300 and PCX5900) thanks to the High Speed Interconnect solution (HSI bridge chip). Back in March in the CeBIT article I briefly talked about the HSI's functions and possibilities with NVIDIA. NVIDIA confirmed that the HSI will work the other way around too and that is precisely the solution they are using.

In the most laymen explanation, you just flip around that HSI-chip and it can be used to make a PCI-Express product compatible with AGP 8x, it works backwards. And it works really well, I might add.

Specs	GeForce 6600	GeForce 6600 GT	GeForce 6800	GeForce 6800 GT	GeForce 6800 Ultra
Codename	NV43	NV43	NV40	NV40GT	NV40U
Transistors	?	?	222 million
Process, GPU maker	110nm	110nm	130nm, IBM
Core clock	300 MHz	500 MHz	Up to 400 MHz	350MHz	400-450 MHz
Memory	128MB DDR1	128MB GDDR3	128MB DDR1	256MB GDDR3	256MB GDDR3
Memory bus	64/128-bit		256-bit
Memory clock	Up to manufacturer	2x500 MHz 2x450 MHz (AGP)	2 x 550MHz	2 x 500MHz	2 x 600MHz
PCB	P212	P212	P2??	P210	P210
Pipelines	8	8	12	16	16
FP operations	FP16, FP32
DirectX	DirectX 9.0c
Pixel shaders	PS 3.0
Vertex shaders	VS 3.0
OpenGL	1.5+ (2.0)
Price	$150	$229	$299	$399	$499
Availability	Oct 2004	Oct/Nov 2004	May/June 2004

As you can unmistakably see there is a product for