PowerEdge: XE8640 with H100 - GPU Performance Issue
Summary: A drop in GPU Performance and "nvsmi-q" log might indicate that hardware Power Brake Slowdown is active.
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Instructions
In some corner cases, the user might come across a poor GPU Performance and the nvsmi-q log might indicate that hardware Power Brake Slowdown is Active.nvidia-smi and GPU_burn log output:
nvsmi-q log output:
Clocks Throttle Reasons Idle : Not Active Applications Clocks Setting : Not Active SW Power Cap : Not Active HW Slowdown : Active HW Thermal Slowdown : Not Active HW Power Brake Slowdown : Active Sync Boost : Not Active SW Thermal Slowdown : Not Active Display Clock Setting : Not Active
nvidia-smi --query-gpu=index,timestamp,power.draw,clocks.sm [clocks.sm],clocks.mem,clocks.gr [clocks.gr] --format=csv -l 1 log output:
Resolution:
Update the BIOS, CPLD, and iDRAC to the latest firmware version. Recent field cases have shown that updating the CPLD to version 1.2.2 and the iDRAC to version 7.10.30 has resolved the issue.
Snippet Post update:
gpu_burn is operating at ~ 300k Gflops, and nvidia-smi shows each GPU ~700W at 100% utilization.
nvsmi-q log output post BIOS update:
Clocks Throttle Reasons Idle : Active Applications Clocks Setting : Not Active SW Power Cap : Not Active HW Slowdown : Not Active HW Thermal Slowdown : Not Active HW Power Brake Slowdown : Not Active Sync Boost : Not Active SW Thermal Slowdown : Not Active Display Clock Setting : Not Active
nvidia-smi & GPU_burn log output post BIOS update:
Affected Products
PowerEdge XE8640Article Properties
Article Number: 000220508
Article Type: How To
Last Modified: 10 Apr 2025
Version: 5
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