The current generation of NVIDIA based graphics cards have rescued them from the disaster caused by the FX series. The stellar high-end cards of this new generation come from the 6800 series and offer unbelievable performance in all the latest games. However, while the high-end market segment was now safeguarded by the 6800 series, NVIDIA also had a secret weapon to take the mainstream market by storm. This weapon that we now know as the GeForce 6600 GT is just as successful as NVIDIA had planned. The 6600 series are the first mid-range native PCI Express solutions offered by NVIDIA.

However, if NVIDIA was to forget about AGP support, then they would be forgetting about the majority of the computers in the world, which still use the interface. Clearly AGP will not be exiting the market anytime soon as most users will not be willing to sacrifice their entire system for a graphics card upgrade. That said manufacturers such as ATi and NVIDIA are still releasing the odd AGP card. While the GeForce 6600 GT was never intended for AGP use, it can be through the NVIDIA HSI bridge chip.

The AGP version of the GeForce 6600 GT is slightly more expensive, possibly due to the bridge chip required to use the older interface. In fact, after doing some quick research I have noticed that many PCI Express cards are around $20 US cheaper than the new AGP versions. Performance wise the AGP and PCIe versions should be much the same, though the PCI Express version will have a slight advantage. This is due to the 100MHz (DDR) higher clock frequency at which the PCI Express cards operate at.

Unfortunately, there are a few draw backs to the new AGP versions other than added cost. The PCI Express GeForce 6600 GT cards were quite popular due to their unique ability to operate in a special mode called SLI. This technology has the potential to drastically boost the performance of the GeForce 6600 GT by using two simultaneously. This new and exciting technology is not featured on the AGP version as there is no chipset that supports dual AGP ports. The PCI Express slot delivered 75watts of power to the graphics card and therefore eliminates the necessity for an additional 4-pin molex power connector. The AGP version does require a power connector as this interface does not supply as much power to the graphics card.

The GeForce 6600 series is still built on the NV43 GPU using the 0.11-micron process. It has all the basic core features of the NV40. Furthermore the 6600 series supports all the latest GeForce features found on the high-end 6800 graphics cards. The pixel pipelines have been halved from 16 of the GeForce 6800 cards, to 8 for the 6600 series. However even with 8, the GeForce 6600 easily out muscles the GeForce PCX series with double the pixel pipelines. With the 8 pipelines and specified clock speeds, the GeForce 6600 GT can produce a memory bandwidth of 14.4GB/s and a 4.0 Billion texels/sec fill rate.

As mentioned earlier, the clock frequencies have also been wound down, reducing the cards memory bandwidth. However, GeForce 6600 does utilize GDDR3 on a 128-bit memory bus in either 128 or 256MB configurations. The GeForce 6600 series comes in three flavors; the standard GeForce 6600 and then the GeForce 6600 GT in both PCIe and AGP versions. The GeForce 6600 will feature a 300MHz core and a 550MHz DDR memory frequency. It has also been said that the manufacturer can configure the memory as they please for the standard GeForce 6600. The GeForce 6600 GT is more high-end and features a core clock of 500MHz and a memory clock of 1GHz or 900MHz for the AGP version.

Todays article will be comparing a number of PCI Express and AGP based GeForce 6600 GT graphics cards. There will be thirteen cards tested from eight different manufacturers. While I will be looking at the performance of all thirteen cards, I suspect it will be much the same. Therefore, I will also be taking the package and price into consideration. Personally, I am more concerned with what comes on and with the graphics card. Things like memory and core cooling are very important to me and this is always a huge focus point.