Dual Monitor Setup

Alright, I just set up a dual monitor thing for the first time. I was planning to connect both of my monitors to my video card, which has a VGA and a DVI input. So I think I'm going to buy a DVI to VGA adaptor and connect the second monitor in through that. But for right now, I have one monitor going into my that video card and the other going into the computer's built-in video card. It works, but not as well as I expected:

1. My computer is running noticeably slower. I know that the resources of a video card are halved if you use dual monitor, but I didn't think that would happen to me since I have each monitor plugged into its own video card. I don't understand. My primary monitor is plugged into the good video card. Can anyone tell me why my computer is running slower and if it would get faster, slower, or stay the same if I plugged both monitors into my good video card?
2. My primary monitor is using a screen resolution 1280x1024, which was the same resolution I was using before I set up this dual monitor thing... but the resolution of my secondary monitor (the one plugged into the inferior video card) is 1280x960 for some reason. That's as high as I can set it to. That's not even a resolution that would fit properly based on the shape of my monitor. And indeed, the display on this monitor looks a little bit weird, especially when looking at text (it doesn't look very sharp). What gives? Am I just not able to set this inferior video card to the resolution I want?
3. I don't know if this has to do with number 2 above, but the colors on the second monitor are also a bit different from the colors on the first monitor, even though they are the same monitors. Again, is it because of the inferior video card?

I have a feeling that my problems from numbers 2 and 3 above would be solved if I bought that adaptor and connected both monitors to my good video card, but again, how would that affect the performance of my computer compared to how it is now?

Here are some specs:

• Windows XP Pro.
• The monitors are both Mag Innovision 765's.
• My "good" video card is a VisionTek Xtasy 9200SE PCI. Like I said, the second monitor is plugged into the crappy built-in video card for now.

I think that you will find your system will return to normal once you get the o/b gfx disabled.

i've run a dual monitor setup now for over a year from an ATI radeon 9250 card, and had the same problem, until i got a DVI to VGA adapter, and disabled my o/b gfx.

Great, I hope you're right.

that solved my problems, and as i said, i have been running for over a year now, with no problems...