I knew I would see some say "Why, or how terrible" 3DMark is, but the initial poster is using it for one of the best reasons. Sure he can't "PLAY" 3DMark, but he can use the score to see how his system is supposed to score, by comparing it to similiar systems.
If his score is only 60% of what others are getting, plain and simple he has something setup wrong in his system!!! Don't blow it off as a useless benchmark. It looks like it's working for him very well. Now he needs to make some changes, and keep testing until it's right.
Imagine if you would that you have a new car. It seems to run great, gets you from here to there a lot better than your old car, and gets decent gas mileage. Must be fine right?
Now you take it to the dragstrip and make some passes on it. Turns out it is much slower than similiar cars. You then make the little adjustment, and now it runs like all the others, and has much more power, and gets much better gas mileage. So one useless test at the dragstip helped out the car that never gets to go fast regularly.