Specs update... Power supply says 800w  I currently use 2 older 23" LGs at1920x1080 and I would move them to the z800

     Jaxon101;  You already have a -matched!- pair of monitors - good.  A decent fairly late model video card should be able to drive those.  I'd get one GPU and not try to do multiple GPUs, so as not to overtax the power supply.  I'm guessing that the HP z800 has a proprietary quick-mount custom fit power supply, so you can't just throw in any old power supply.  My refurb Urania is it's little sister, the midtower z600.      When shopping for a video card, note what ports each card has, and what ports your monitors have.  The nVidia Quadro FX3800 in Urania has one DVI and two DisplayPorts;  so I use one DVI-D cable and the other cable is DVI-D to DisplayPort, to run the DVI-D ports on both monitors.  For 1920x1080, you could use DVI, DisplayPort, or HDMI and get full resolution.  Avoid relying on the blue VGA (aka "Dsub", "DE15", etc) which does not have as much resolution capacity as the others.  HDMI tops out at 1920x1200, DVI-D will run 2560x1600, and DisplayPort will support 4K monitors.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5