I would think that the fact that you've had more offers to purchase/trade the card than you have had help on the problem would keep you interested in keeping the card.
Have you tried installing the Sapphire drivers vs the Catalyst drivers? I had a similar problem with performance and TV Out with my MSI GeForce Ti200 128MB card when I tried to use the Detonators, but when I used MSI's drivers, it worked without complaint.
More to the point, have you called their Tech Support number?
http://www.sapphiretech.com/contacts/contact.asp
Also, which version of Windows are you running?
I find it odd that your 3dMark scores are so low, even if it is a synthetic benchmark, as currently ALL of the top 10 people use insanely overclocked P4/AthlonXPs with Radeon 9700 Pros in them. #5 happens to be a Sapphire card as well.