Multithreading successfully went mainstream when AMD released it's X2 line of processors for the desktop. The industry as a whole is warming up to the use of multiple physical processors to teraflop their way past calculative obstacles. Parallel processing has been a mainstay of GPU systems for a long time, and the revival of multi-GPU processing in the GeForce 6 series of NVIDIA graphics accelerators have prompted some further developments of multi-GPU rendering. Whether or not you prefer to stack greens or reds in your sandwiches, both the cabbage and tomato farmers have been busy working to make superior chomp-chump for the enthusiasts amongst the many. - VR-Zone

Inno3D GeForce 9800 GX2 Multi-GPU Version Review

After the considerably successful launch of the ATI Radeon HD3870 X2, our friends at NVIDIA have been busy trying to come up with a serious rendering monster. The NVIDIA GeForce 9800 GX2 is what we would term a SLI package involving some very nifty engineering workaround to tackle cumbersome politics within the computer hardware industry. Based on the G92 GPU, the GeForce 9800 GX2 design puts multi-GPU in any system with less pushy support, the same way the Radeon HD 3870 X2 and GeForce 7950 GX2 did. What these GPU packages do, is market multi-GPU rendering as a single add-in-card.

The Inno3D GeForce 9800 GX2 depends on the reference PCB and thermal design from NVIDIA. Clad in a gloss black metal jacket, this graphics accelerator is actually electrically shielded. The HDMI and dual DVI ports are the escape routes for frisky pixels, while a SLI port is present for you to run quadruple GPU's. Naturally, such a design takes up two expansion slots. Consisting two physical circuit boards, the NVIDIA GeForce 9800 GX2 falls into the heavy weight category. Found along the GPU rim are 1.0ns Samsung memory that runs on a 256-bit memory controller, totalling 1024MB of frame buffer memory.

Squishing a pair of GPU chipsets together to form a single dual slot graphics accelerator is no mean feature, especially if you think of it as an act of melting a pair of GeForce 8800 GTS 512MB into one. Melting, is exactly what will happen if the design thermals are not taken care of. Then again, heat isn't going to be a tripping stone for NVIDIA this time around. Back when the NVIDIA GeForce 7950 GX2 was released, the front to back design proved to be an engineering challege for thermal management. Enough surface area had to to be garnered from a heatsink half the width of an expansion slot, while noise had to be kept in check.

The power consumption of the two modules combined takes a fair few amperes, which has to be supplied via the dual PCI Express power sockets. For this a 3-phase power is available for both G92 chipsets, based around a Volterra power system. At its heart is the Volterra power management controller, which has already been seen on a few generation of ATI graphics accelerators. Power delivery is replicated on both modules.