Remove a rear H100/H200 GPU

Follow instructions in this section to remove a rear H100/H200 GPU. The procedure must be executed by a trained technician.

About this task

Attention

• Read Installation Guidelines and Safety inspection checklist to ensure that you work safely.
• Power off the server and peripheral devices and disconnect the power cords and all external cables. See Power off the server.
• If the server is installed in a rack, slide the server out on its rack slide rails to gain access to the top cover, or remove the chassis from the rack. See Remove the server from rack.
• Two people and one lifting device on site that can support up to 400 lb (181 kg) are required to perform this procedure. If you do not already have a lifting device available, Lenovo offers the Genie Lift GL-8 material lift that can be purchased at Data Center Solution Configurator. Make sure to include the Foot-release brake and the Load Platform when ordering the Genie Lift GL-8 material lift.
• A torque screwdriver is available for request if you do not have one at hand.

Note

Make sure you have the required tools listed below available to properly replace the component:

• Torx T10 head screwdriver
• Torx T15 head screwdriver
• Phillips #1 head screwdriver
• Phillips #2 head screwdriver
• Flat head screwdriver
• Alcohol cleaning pad
• H100/H200 PCM Kit
• SR780a V3 water loop putty pad kit
• SR780a V3 water loop service kit

Important

Putty pad/phase change material (PCM) replacement guidelines

• Before replacing the putty pad/PCM, gently clean the hardware surface with an alcohol cleaning pad.
• Hold the putty pad/PCM carefully to avoid deformation. Make sure no screw hole or opening is blocked by the putty pad/PCM.
• Do not use expired putty pad/PCM. Check the expiry date on putty pad/PCM package. If the putty pads/PCM are expired, acquire new ones to properly replace them.

The following illustration shows the GPU numbering and corresponding slot numbering in XCC.

Figure 1. GPU numbering

Procedure

1. Make preparation for this task.
   1. Remove the front top cover. See Remove the front top cover.
   2. Remove the rear top cover. See Remove the rear top cover.
   3. Remove the fan cage. See Remove the fan cage (trained technician only).
   4. Remove the CPU complex. See Remove the CPU complex.
   5. Remove the power complex. See Remove the power complex.
   6. Disconnect the cables and remove them from the GPU complex if necessary. Before disconnecting the cables, make a list of each cable and record the connectors the cable is connected to. Refer to Internal cable routing.
2. Locate the rear GPU.
3. Remove the leakage sensor module cable from the cable clips, route it away from the cold plate, and reinstall it in the cable clips adjacent to the cold plate.
   Figure 2. Removing the leakage sensor module cables
   
   
4. Follow the screw sequence specified on the cold plate label, and fully loosen the four Torx T10 screws with a torque screwdriver set to the proper torque.
   Note

   Loosen or tighten the screws with a torque screwdriver set to the proper torque. For reference, the torque required for the screws to be fully loosen or tighten is 0.4±0.05 newton-meter, 3.5±0.5 pound-inch.
   Figure 3. Removing the GPU cold plate
   
   

   Note

   If necessary, use a flat screwdriver to gently separate the cold plate and the GPU from the corner of the cold plate. Ensure not the damage the GPU or the cold plate.
5. Install the service bracket onto the GPU cold plate.
   1. Align the two guide pins at the bottom of the service bracket with the guide holes on the GPU cold plate; then, lower it onto the cold plate.
   2. Fasten the captive screw (PH1, 1 x M3, 0.5 newton-meters, 4.3 inch-pound) to secure the service bracket to the cold plate.
      Figure 4. Installing the service bracket onto the GPU cold plate
      
      
6. Install the service bracket and the GPU cold plate assembly onto the rear H100/H200 GPU cold plate module manifold.
   1. Flip over the service bracket and the GPU cold plate assembly; then, align the captive screw and two guide pins with the screw hole and guide holes on the manifold.
   2. Fasten the captive screw (PH1, 1 x M3, 0.5 newton-meters, 4.3 inch-pound) to secure the service bracket and GPU cold plate assembly onto the manifold.
      Figure 5. Installing the service bracket and the GPU cold plate assembly
      
      
      Note

      Ensure to install the service bracket and GPU cold plate assembly in the screw holes and guide holes corresponding to the specific GPU slot number.

      Figure 6. Service bracket and GPU cold plate assembly installation location
      
      
7. Immediately clean the PCM and putty pads off from the GPU with alcohol cleaning pads. Gently clean the PCM and putty pads to avoid GPU damages.
   Attention

   • It is recommended to clean the PCM while it is in liquid state.

   • The electrical components around the die on the GPUs are extremely delicate. When removing the PCM and cleaning the GPU die, avoid touching the electrical components to prevent damage.

   Figure 7. Cleaning PCM and putty pads off from the GPU
   
   
8. With alcohol cleaning pads, wipe off any remaining putty pad and PCMs from the GPU cold plate.
   Figure 8. Wiping PCM and putty pads off from the cold plate
   
   
9. Remove the GPU.
   1. Unfasten the four Torx T15 screws in the sequence shown in the illustration below.
      Note

      Loosen the screws with a torque screwdriver set to the proper torque. For reference, the torque required for the screws to be fully loosen is 0.6 newton-meters, 5.3 inch-pounds.
   2. Remove the GPU from the GPU baseboard.
      Figure 9. Removing the GPU