The G200 is tremendously complex. Coupled with the imperfect tech process, this limited the clock rates of the senior model of the GeForce GTX 200 series to 600MHz (main domain) and 1300MHz (shader domain). That’s not high for the year of 2008. For comparison, the previous-generation core, even in the 65nm version, was clocked at 678/1688MHz. Experiments show that the G92 core (GeForce 8800, 9800) can be stable at frequencies of 800/2000MHz and higher if you increase its voltage and provide enough cooling.

Without a doubt, the G200 must have some frequency reserves, too. And these reserves can be called for in order to compete with the Radeon HD 4870 X2.

This must be the reason why Zotac has released an overclocked version of GeForce GTX 280 in its AMP! series. Such pre-overclocked cards were expected because overclocking is in fact the only way of marketing a unique G200-based card. We don’t think any maker will release a GeForce GTX 280 with a unique PCB design because developing a PCB with a 512-bit memory bus is quite a daunting task.

So, today we will be testing the Zotac GeForce GTX 280 AMP! in games to see how an overclocked G200 compares with two RV770 cores combined.

http://www.xbitlabs.com/articles/vid...gtx280amp.html