2 video cards vs 1, for 2 monitor output

I currently have 2 geforce 210 1gb cards (1 in x16 slot and the other in x4 slot) running 1 monitor each. My monitors only support vga and dvi input, so i have each monitor connected to each card's dvi ouput. Each card supports dual monitor output, but when i built the system, getting an extra card was cheaper than an hdmi-to-dvi adapter -- hence the two cards.

I recently purchased a fanless heatsink for the cpu, but realized that installing it would require removing the x16 video card for space. So if i want to use the heatsink, i'll have to connect both my monitors to the card in the x4 slot.

I don't do any gaming, and rarely run video-intensive applications. Most of the time, I work with large dynamic spreadsheets, spanning both monitors, and watch the occasional movie. I rarely do video or image editing, but it happens.

My question is: will removing the x16 card and running both monitors through the remaining x4 card affect image quality or performance in ANY way?

Many thanks in advance for your input!