You can stack up the cpu-boxes and connect to just one monitor and use the switch box to select the host. This saves space and you eliminate monitor(200 US dollars), keyboard(60 dollars) and the mouse(50 dollars) and also avoid lot of clutter.
Please check out these sites:
Search engine yahoo to find more companies with "Server Switches" or "KVM Switches".
It is strongly recommended to have a dedicated unix box for each PostgreSQL server process for better performance. No other application program/processes should run on this box. See the Business section of your local newspapers for local vendors selling only intel box, 13" monochrome monitor (very low cost monitor). Local vendors sell just the hardware WITHOUT any Microsoft Windows/DOS (saves you about $ 150). You do not need a color monitor for the database server, as you can do remote administration from color PC workstation. Get Redhat Linux cdrom from below -
To stack up cpu boxes, buy $ 15 floor-to-ceiling shelf and clamp it to the wall with several bracket clamps. Also bolt it down to floor. The size of the shelf is such that it just fits the computer. Place Intel boxes such that the side is butting against the wall and the front and rear (serial ports, network port, power connections) are easily accessible. Follow rules of Ergonomics, the shelf should have enough gap on both sides and there should be enough gap between many tower shelves. Bundle the wires neatly. Put vertical steel strips so that boxes do not fall off during earth-quakes. Floor to ceiling shelf will fit about 30 Intel-Linux boxes. Thus a small room can fit about 10 tower shelves with 300 cpu boxes controlled by just one monitor and one keyboard!!
Below is the extract from networktechnic Inc for the "Server Switches"
Order now call 800-742-8324 (toll free in USA) To receive our catalog please Email your address to: email@example.com CONTROL MULTIPLE PC'S with one keyboard monitor & mouse These electronic switches will allow one keyboard, monitor & mouse to control up to 64 PC's. Embedded microcomputers simulate the presence of keyboard, monitor & mouse to all attached PC's 100% of the time. Features and Applications * Keyboard, front panel or remote control * 9 pin D Serial or 6 pin miniDIN mouse support * 5 pin DIN or 6 pin miniDIN keyboard support * 1600x1200 video resolution with no degradation * Uses standard cables * Desktop or rackmount Specifications - Keyboard * All connectors are female * 5 pin DIN or 6 pin miniDIN * Will hard or soft boot all PC's 100% of the time Controls - Buttons on Front * Touch a button and be connected to that PC * Hold any button in for more than 0.5 second and go into SCAN, BROADCAST or COMMAND mode * LEDs on front indicate mode of operation Keyboard * Type CTRL+* and go into COMMAND mode * SCAN, BROADCAST or COMMAND are available Mouse * 9 pin D serial o NTI switch emulates Microsoft serial mouse to all PC's o 9 pin D male for mouse o 9 pin D female for PC's * 6 pin miniDIN o NTI switch emulates IBM PS/2 style mouse to all PC's o All connectors are female Wired remote * Optional--must be purchased * Operates same as "Buttons on Front" Tech Info * Request technical manual MAN025 Monitor-VGA * Bandwidth is 150 MHz * 1600X1200 resolution with no degradation * All connectors are female Power * 110 or 220 VAC at 50 or 60 Hz