Setting up a poker station

[BasketballNYC]

I have been playing online for a couple of years with a laptop that could just barely handle PP, PT and GT+. I am now up to 6 tabling and the PT db has gotten bigger and the laptop can't handle it. I want to put together a new setup with a desktop and multiple monitors.

What power machine do I need to 6-8 table with GameTime+ running without it getting sluggish? Also what is the best way to set up multiple monitors? Should I just buy some cheap PCI video cards and put them in the computer or buy a multi card? And where are good places to buy these parts cheap? Thanks for the help.