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- HP Community
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- Adding Processor

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01-12-2025 09:52 AM
Welcome to our HP Community forum!
The HP Z6 G4 Workstation is a dual-processor-capable system, but it doesn’t "stack" processors. Instead, it has two separate CPU sockets on the motherboard. If you are seeing only one heatsink installed, it means the system currently has a single processor configuration, but the second CPU socket is still present on the motherboard, albeit unused.
Key Points:
Dual-Processor Design: The HP Z6 G4 motherboard includes two CPU sockets (CPU0 and CPU1). The default configuration usually comes with one processor (CPU0) installed.
Installing a Second Processor:
- You’ll need an additional processor kit that includes a CPU, a heatsink, and possibly a fan assembly.
- The second processor does not "stack" on top of the first. Instead, it goes into the secondary CPU socket on the motherboard.
Heatsink and Cooling:
- Each CPU requires its own dedicated heatsink. If there is only one heatsink currently installed, it's for the primary CPU.
- The second CPU socket will be empty, and you'll need to install a second heatsink over it.
Processor Matching:
- Both processors must be of the same model and stepping to ensure compatibility.
- Confirm the exact specifications of your existing processor and purchase a compatible one.
BIOS/Hardware Configuration:
- Once the second processor is installed, the system’s BIOS should recognize it automatically. Ensure your BIOS is up to date to support dual CPUs.
The second CPU socket is located on a riser card that must be installed into the motherboard. This riser card provides the additional socket for the second processor. If your system currently has only one processor, it may not include this riser card.
To install a second processor, you'll need to acquire and install the appropriate riser card, processor, and heatsink. It's important to ensure compatibility with your existing system components.
For a visual guide on installing the secondary processor and heatsink, here you go: https://youtu.be/E_8ZPcJXgGw.
Kind Regards,
NonSequitur777
01-12-2025 10:08 AM
The part number for the HP Z6 G4 Workstation second CPU riser card is typically one of the following, depending on the configuration and region:
- 844782-001: Riser card for the second CPU, often bundled with a heatsink.
- 935686-001: Another commonly listed part number for the riser assembly.
- 900199-001: May include the riser card, heatsink, and associated components.
Kind Regards,
NonSequitur777