Remove the water loop

Use this information to remove the water loop in the SD665-N V3 tray.

Procedure

1. Make preparations for this task.
   1. Remove the tray from the enclosure. See Remove a DWC tray from the enclosure.
   2. Remove the tray cover. See Remove the tray cover.
   3. Remove the cross braces. See Remove the cross braces.
   4. Remove the DIMM comb. See Remove a DIMM comb.
   5. Remove memory modules. See Remove a memory module.
   6. Remove the M.2 backplane assembly. See Remove the M.2 backplane assembly.
      Note

      The M.2 backplane cold plate needs to be removed as well.
   7. Remove the bus bar. See Remove the bus bar.
   8. Remove the MCIO cables. Follow the guidance and routing information in Internal cable routing.
   9. Remove the drive cage. See Remove a drive cage assembly.
   10. Remove the OSFP module. See Remove the OSFP module.

Separate the water loop from the GPU node.

2. Remove the carrier board power cable from the GPU node.
   Figure 1. Carrier board power cable removal
   
   

   Cable	From (carrier board)	To (GPU node power distribution board)
   1 Carrier board power cable	Power and side band connector	Power connector

3. Remove cable tie from the GPU board.
   Figure 2. Cable tie removal
   
   
4. Remove the Hex screw (x1) and the PH1 screws (x3) from the water loop with a torque screwdriver set to the proper torque.
   Note

   For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

   Figure 3. Water loop Hex and PH1 screws removal (GPU node)
   
   
5. Remove water loop screws and quick connect screws (x13 Torx T10 screws) with a torque screwdriver set to the proper torque.
   Note

   For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

   Figure 4. Water loop Torx T10 screws removal (GPU node)
   
   
6. Remove the quick connect screws (x4 Torx T10) with a torque screwdriver set to the proper torque.
   Note

   For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

   Figure 5. Quick connect screw removal (GPU node)
   
   
7. Follow the screw removal sequence specified on the network board label, and remove network cold plate screws (x8 Torx T10 screws) with a torque screwdriver set to the proper torque.
   Note

   For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

   Figure 6. Network card screw removal
   
   
8. Loosen GPU cold plate screws (x16 Torx T10 screws) in the diagonal pattern with a torque screwdriver set to the proper torque.
   Note

   For reference, the torque required for the screws to be fully tightened/loosened is 0.4+/-0.05 N-m, 3.5+/-0.5 lb-In.

   Figure 7. Loosening GPU cold plate screw
   
   
9. Release the front and rear MISC conduction plates of the water loop from the GPU board.
   1. Insert a flat head screwdriver into the gaps between the MISC conduction plates (front and rear) and the GPU board. Then, slightly rotate the flat head screwdriver.
      Note

      Locations of the gaps for inserting flat head screwdriver is shown in the illustration below.
   2. The front and rear MISC conduction plates release from the GPU board slightly.
      Figure 8. Releasing the front and rear MISC conduction plates release from the GPU board
      
      
10. Release the GPU cold plates from the GPUs.
    1. There are notches on the sides of the GPU cold plates for inserting a flat head screwdriver. The locations of the notches are shown in the illustration below.
       Attention

       Inserting the flat head screwdriver ONLY to the notches circled in the illustration below. Otherwise, the screwdriver may damage the GPUs.

       Figure 9. Notches for releasing GPU cold plates
       
       
    2. Insert a flat screwdriver into all the notches shown in the illustration; then, slightly rotate the screwdriver to release the GPU cold plates from the GPUs.
       Figure 10. Releasing the GPU cold plate from the GPU
       
       
11. Gently put the water loop carrier down onto the water loop and ensure it is seated firmly on the water loop.
    Figure 11. Water loop carrier installation (GPU node)
    
    
12. Tighten water loop carrier screws (x20 Phillips #2 screws) with a torque screwdriver set to the proper torque.
    Note

    For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

    Figure 12. Water loop screw and quick connect screw removal (GPU node)
    
    
13. Carefully rotate the GPU node side water loop so that it is sitting on top of the Compute node side water loop.
    Figure 13. Folding the GPU node side water loop onto the Compute node side water loop
    
    
14. Immediately clean the PCM off all the GPUs with alcohol cleaning pads. Gently clean the PCM 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 damages.

    Figure 14. Cleaning PCM off from all GPUs
    
    
15. With alcohol cleaning pads, wipe off any remaining putty pad and PCMs from the water loop and components in the GPU node.
    Figure 15. Cleaning putty pads from water loop
    
    
16. Flip the GPU node water loop back to the GPU node.
    Figure 16. Flipping GPU node water loop to the GPU node
    
    

Separate the water loop from the compute node.

17. Remove the two Hex screws from the OSFP module with a 4.5 mm hex head screwdriver.
    Figure 17. OSFP module conduction plate Hex screws removal
    
    
18. Remove the OSFP module conduction plate. With alcohol cleaning pads, wipe of any remaining putty pads from the conduction plate.

    Screw Type	Screwdriver Type
    1 M3x5 screw (x3)	Phillips #1 head screwdriver
    2 M3 screw (x2)	T10 screwdriver

    Figure 18. OSFP module conduction plate removal
    
    
19. Remove the five Torx T10 screws to loosen the quick connect.
    Note

    For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

    Figure 19. Quick connect screw removal (Compute node)
    
    
20. Remove water loop screws and quick connect screws (14x Torx T10 screws per node) with a torque screwdriver set to the proper torque.
    Note

    • For reference, the torque required for the screws to be fully tightened/removed is 5.0+/- 0.5 lbf-in, 0.55+/- 0.05 N-M.

    • When removing the 1 VR cold plate screws (x2), remove the washers, too. Make sure to keep the washers for future use.

      Figure 20. VR cold plate screws with washer
      
      

    Figure 21. Water loop screw removal

    1 VR cold plate screws (x2)

    
    
21. Remove processor cold plate screws (12x Torx T20 screws per node). Follow the screw sequence specified on the processor cold plate label and loosen the screws with a general screwdriver. Fully loosen each screw; then, proceed to the next screw.
    Note

    For reference, the torque required for the screws to be fully tightened/removed is 1.12-1.46 newton-meters, 10-13 inch-pounds

    Figure 22. Processor cold plate label

    Fully loosen each screw in this order: 6 > 5 > 4 > 3 > 2 > 1

    
    
    

    Figure 23. Processor cold plate removal
    
    
22. Orient the water loop carrier with the guide pin; then, gently put the water loop carrier down and ensure it is seated firmly on the water loop.
    Figure 24. Water loop carrier installation (Compute node)
    
    
23. Tighten water loop carrier screws (x12 Phillips #2 screws).
    Note

    Select screw holes marked as R on the rear of the shipping bracket.

    Figure 25. Water loop carrier screws installation (Compute node)
    
    
24. Rotate the latch on the water loop carrier to separate the water loop from processors.
    Figure 26. Separate water loop from processor
    
    

Securing two water loops with shipping brackets together.

25. Carefully rotate the water loop so that the Compute node side water loop is sitting on top of the GPU node side water loop.
    Figure 27. Folding the water loop
    
    
26. Fasten two captive thumbscrews to secure water loop carriers to each other.
    Figure 28. Tightening captive thumbscrews
    
    
27. Carefully lift the water loop up off the system board and out of the node.
    Figure 29. Water loop removal
    
    
28. With alcohol cleaning pads, wipe off any remaining putty pad from the water loop and components in the compute node