內幕就是，
Det.50裡面有太多令Valve看不下去的cheat。

http://www.extremetech.com/print_ar...,a=61435,00.asp
原文節錄如下:

nVidia has been circulating its Det50 driver to analysts in hopes that we would use it for our Half-Life 2 benchmarking. The driver contains application-specific optimizations that will likely improve nVidia's overall performance picture, however Valve's Gabe Newell expressed concerns that some of nVidia's optimizations may go too far. Doug Lombardi of Valve has explicitly asked that beta versions of the Det50 drivers not be used for benchmarking.

大意:
NVIDIA準備在Det50裡面加入針對針對HL2 benchmark "優化"的程式碼。
Valve公司的Gabe Newell認為某些優化的手段"太過火"，
Doug Lombardi(from Valve)更明確指出不要拿Det50來跑benchmark。