GeForce 7900GTX 512MB cards typically run core
clock speeds around 650MHz, meaning the 7900GX2 is significantly under clocked.
However, there are two cores present.
NVIDIA's GeForce 7950GX2 is a dual PCB adaptor that is directly derived from
the GeForce 7900GX2, which was already derived from the GeForce 7900GTX
ASIC. GeForce 7950GX2 takes two GeForce 7900GTX boards, and joins them
via 32 PCIe lanes. 16 additional lanes are routed to the motherboard out
to the PCIe adaptor. The GeForce 7900GX2 was designed specifically for
OEM system builds and as a result nothing was compromised for
performance. However, GeForce 7950GX2 is designed to be the retail component,
and as such a few things needed tweaking for retail sales.
For example, the cooler on the 7900GX2 has been drastically redesigned and
reduced for the 7950GX2. Gone is the large copper heatsink/fan combo in
favor of a much smaller aluminum heatsink with a more powerful fan.
Furthermore, the majority of the mosfets and capacitors positioned at the rear
of the card have been moved toward the DVI inputs instead, allowing engineers
to cut down the size of the PCB substantially, down to nine inches. It's also important to note that the SLI bridge is not present on the 7950GX2.
NVIDIA plans to target the Radeon X1900XTX with the 7950GX2 launch. Both
cards are approximately the same size and both consume two expansion slots in a
standard chassis. The marketing marterial bundled with the 7950GX2 claims that a full system using a Radeon X1900XTX requires just under 400W
during peak operation, while a 7950GX2 system will only consume 358W and still provide greater performance.
Like the GeForce 7900 and 7600, 7950GX2 has HDCP support built into the
PureVideo portion of the 7950 ASIC. However, once again, it’s up to the
manufacturers to incorporate the CyptoROM for HDCP keys. Without this
additional chip, the GeForce 7950GX2 cannot do DVI-HDCP.
The NVIDIA GeForce 7950GX2 graphics card will launch on June 6, and will retail
for $599-649. Even though the card is designed for QUAD SLI, there will
be no four-GPU support at the time of launch with the 7950GX2 due to driver
constraints. ATI's Radeon X1900XTX retails for approximately $480 USD.
Update 05/27/2006: You can still view the original performance scaling image here. We originally reported that the 7950GX2 would require SLI to work, but this is only true of QUAD SLI performance.