SPEC CPU2017 Platform Settings for GIGA-BYTE
- Determinism Slider:
-
Selects the determinism mode for the CPU:
- Power: Maximizes performance within the power limits defined by cTDP and PPT.
- Performance: Provides predictable performance across all processors of the same type.
- Global C-state Control:
-
Controls IO based C-state generation and DF C-states.
- cTDP Control:
-
Configures the maximum power that the CPU will consume, up to the
platform power limit (PPT). Valid values vary by CPU model. If value
outside the valid range is set, the CPU will automatically adjust the
value so that it does fall within the valid range. When increasing cTDP,
additional power will only be consumed up to the Package Power Limit
(PPT), which may be less than the cTDP setting.
| Model | Minimum cTDP | Maximum cTDP |
|---|
| EPYC 7742 | 225 | 240 |
| EPYC 7702 | 165 | 200 |
| EPYC 7702P | 180 | 200 |
| EPYC 7452 | 155 | 180 |
- Package Power Limit (PPT) Control:
-
Specifies the maximum power that each CPU package may consume in the system. The actual power limit is the maximum of the Package Power Limit and cTDP.
- NUMA nodes per socket:
-
Specifies the number of desired NUMA nodes per populated socket in the system:
- NPS1: Each physical processor is a NUMA node, and memory accesses are interleaved across all memory channels directly connected to the physical processor.
- NPS2: Each physical processor is two NUMA nodes, and memory accesses are interleaved across 4 memory channels.
- NPS4: Each physical processor is four NUMA nodes, and memory accesses are interleaved across 2 memory channels.
- SMT Mode:
-
Can be used to disable symmetric multithreading. To re-enable SMT, a POWER CYCLE is needed after selecting the 'Auto' option. WARNING - S3 is NOT SUPPORTED on systems where SMT is disabled.
- IOMMU:
-
Enable: Enables the I/O Memory Management Unit (IOMMU), which extends the AMD64 system architecture by adding support for address translation and system memory access protection on DMA transfers from peripheral devices.
- Enforce POR:
-
By default, POR (CPU system limits) are enforced by default. To override them, it is necessary to set this option to "Accept".
- Memory Overclocking:
-
GIGA-BYTE supports memory overclocking, so that PC4-3200 memory can run at 3200 MT/s even in 2DPC configurations. In order to change this, "Enforce POR" must be set to "Accept". Then the "Overclock" option becomes visible, and it must be set to "Enabled". This allows the Memory Clock Speed to be adjusted. Units are MHz, which is half the number of transfers/s that the DDR4 memory will support.
Note that the DIMMs installed in the system must be rated for the selected memory clock speed, so a setting of "1600MHz" requires PC4-3200 DIMMs.