Yes there will be a bottleneck, but it depends on the game.
CPU-intensive games such as GTA4, Starcraft2, etc will experience a bottleneck that might be noticeable.
There will be a bottleneck in FarCry2, etc but mainly in fps recording rates.
There won't be a noticeable bottleneck in Crysis at higher resolutions.http://www.tomshardware.com/reviews/balanced-gaming-pc-overclock,2625-9.html
Two GTX460s are comparable to the 5970. Your 3.8GHz CPU will be weaker than the OCed E8400 @ 4.4GHz due to the 600MHz difference and 3mb less cache. So if there are bottlenecks for the OCed E8400 + 5970, there will be greater bottlenecks for your system.