As long as you are happy with it running at 38fps, that is fine.
To tell the truth, 38fps should be smooth to the eyes anyway, and so as long as you are happy, whats the problem?
Its just basically how many frames at that detailed setting the card can throw out in a second, and 38fps is very good in my opinion for any new game at a high resoloution like that.
A TAD BIT MORE INFO:
I mean, you could get a new card, and at that resoloution, be getting 80fps+ but you probably wouldn't notice the difference from 60.
It'd just tell you that the card has alot more to offer for new games, where it'll be pushed harder still to its limits.
I mean, on really new cards, people re asked to put on Vertical Sync which stops the video card going any faster than the monitors refresh rate (Usually 60fps) at all times to stop the game going too fast.
Many games set a limit anyway.