I have two and it works fine. Windows 2000 will support a max of 10 adapters. so 4 should work fine as long as ther are no driver conflicts. good luck. Pleas eread on.
Installation of Multiple Display Adapters with Windows 2000
NOTE: Windows 2000 supports a maximum of 10 adapters.
Turn on your computer and log on to Windows 2000.
Click Start, point to Settings, click Control Panel, and then double-click Display.
On the Settings tab, confirm that your display adapter is listed correctly.
NOTE: If your display adapter is listed as VGA, you cannot configure you computer for multiple monitors. Contact the manufacturer of your display adapter to see if you can obtain a Windows 2000 driver.
Make sure that the color depth is set to at least 256 colors (16 BPP is recommended).
Shut down the computer.
Before you insert your secondary display adapter, confirm that it has VGA-disabled selected. (This is done with either a jumper or a small dip switch located on the secondary display adapter. If you cannot locate a jumper or switch, then consult the manufacturer's documentation or contact the manufacturer for more information.)
Insert your secondary display adapter into an available PCI slot and connect a second monitor to the secondary display adapter.
Turn on both the monitors, start the computer, and allow the computer to start into Windows 2000. You should see the computer post on the primary video card. When you log on, Windows 2000 detects your new display adapter and installs the appropriate driver for your display adapter and monitor if your monitor is Plug and Play.
Right-click a blank portion of your desktop, and then click Properties.
On the Settings tab two monitor icons are displayed. Click the new monitor, and then click Extend my Windows desktop onto this monitor.
NOTE: You can use these steps to install additional adapters.