OK, E-2000 gave me a different looking box altogether.
I can't tell what size the box is in your image.
A standard ATX box is 8" wide and the drives mount horizontally.
They can be mini-tower, mid-tower and full tower, etc.
The height and the length is variable.
That's not as important as your existing power supply and its design.
Also, does your box accept [highlight]full-height cards[/highlight] or do you have to use[highlight] low-profile[/highlight].
And then, of course, do you have the correct card to begin with ?
[highlight]1.[/highlight] Verify the video card for fitment in your box.
[highlight]2.[/highlight] Contact Gateway and ask if your power supply (and its connectors) are mainstream or not.
You need to establish if it's proprietary or not.
[highlight]3.[/highlight] You may get nowhere on item two, especially if they switch you to Dave in Bombay.
So, try contacting PC Power and Cooling they may have a solution.
It won't be cheap, but it will be bulletproof if they have something.