It's been discussed before in another thread. Things to consider: 1) Purchase price. 2) Replacement cost. 3) Impact to productivity. This is if/when one of your video cards go south. 2 quad cards. Each quad card: $375. About $90 per monitor. Replacement cost: $375. If one goes down, 50% impact. 4 dual cards. Each card: $50. About $25 per monitor. Replacement cost: $50. If one goes down, 25% impact.
HDMI is electrically compatible with the signals used by Digital Visual Interface (DVI). HDMI carries 2 more channels for audio. DVI no audio. In a sense HDMI is better - only if your monitor has the HDMI input jack. Or else you would need to buy a converter cable HDMI to DVI, one cable per monitor. So the best is to match what your monitor has for input. http://en.wikipedia.org/wiki/HDMI
My question regarding hdmi input for monitors is regarding the clarity of charts. Is it better to have charting running off hdmi monitors or dvi connected monitors?
They are the same. Both are digital. The resolution for the image quality is defined by your video card - under your control in Window's control panel. (e.g. 1920 x 1080, or 1280 x 1024, etc.) Doesn't matter whether the signal goes through the HDMI cable or the DVI cable.