Use the HP Z640/Z840/Z8G4 Rail Rack Kit to rack mount your HP Z640, HP Z840 or HP Z8 G4 Workstation. It features new inner rails, additional mounting holes, and new front flanges vs. the predecessor kit.
The HP Z4 G4 Memory Cooling Solution can be installed on any HP Z4 G4 Workstation configuration for improved system acoustics, but it is required for dual-processor configurations and configurations with greater than 32 GB total system memory.