For business desktop use, I prefer onboard graphics for reliability. Also, most add-in cards require fans for cooling which gives you another point of failure while adding to the noise. Power requirements are higher when you want the graphics performance of the faster graphics cards.
For server use, you can get FX boards and install a very cheap video card with low power requirements and no fan. That's actually also my current desktop configuration (uses an HD6450 card with large heatsink) as well. Not running games, I find it works nicely.
RegardsMichael Fothergill