The Aten CS1754 4-Port PS/2 - USB KVM Switch is a KVM Switch with 4 ports and supports computers with PS/2 or USB interfaces, and supports 3-tier connection via cascade. With 21 units, you can control up to 64 computers.
One USB console controls 4 computers with speaker and microphone support
Cascadable up to 3 levels - supports up to 64 computers
Dual interface supports computers with PS/2 or USB keyboards and mice
Auto PS/2 and USB interface detection
Buzzer on/off via hotkey and OSD
Computer selection via front panel pushbuttons, hotkeys, and OSD
Supports resolutions up to 2048 x 1536; DDC2B
Firmware upgradable
USB ASIC inside
Rack mountable in 19" system rack
Multiplatform support
UPC: 672792001840