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System Setup Screen | BIOS Attribute Name | BIOS Default Setting | Description |
Processor Settings | Logical Processor | Enabled | Enable or disable the logical processors (Hyper-Threading Technology) |
| CPU Interconnect Speed | Maximum data rate | This setting governs the frequency of the communication links among the CPUs in the system. Standard and basic bin processors support lower link frequencies than the advanced parts. Maximum Data Rate indicates that the BIOS chooses the communication links at the maximum frequency that the processor supports. Specific processor frequencies can also be selected. For best performance, select the Maximum Data setting. Any reduction in the communication link frequency affects the performance of nonlocal memory accesses and cache coherency traffic. In addition, it can reduce access speed to nonlocal I/O devices from a CPU. However, if power-saving considerations outweigh performance, reduce the frequency of the CPU communication links. Note: It is important to localize memory and I/O accesses to the nearest NUMA node to minimize the impact to system performance. |
Virtualization Technology | Enabled | When this option is Enabled, BIOS enables the processor virtualization features. | |
Sub NUMA Cluster | Disabled | Sub NUMA Clustering (SNC) is a feature for breaking up the Low Latency Compute (LLC) into disjointed clusters and is based on address range. Each cluster is bound to a subset of the memory controllers in the system. It improves average latency to the LLC | |
MADT Core Enumeration | Round Robin | Specifies the MADT Core Enumeration. This option is set to default in Round Robin. The linear option supports industry core enumeration, whereas the Round Robin option supports Dell optimized core enumeration. | |
UPI Prefetch | Enabled | UPI Prefetch is a mechanism to get the memory read started early on the DDR bus. The UPI Rx path spawns a MemSpecRd to the integrated Memory Controller (iMC) directly. | |
XPT Prefetch | Enabled | This option is set to Enabled by default. | |
LLC Prefetch | Enabled | Enables or disables the LLC Prefetch on all threads. This option is set to Enabled by default. | |
Dell Controlled Turbo | Disabled | Enables control of the turbo engagement. It sets the maximum turbo ratio limit and is based on the number of active cores. This option is active only when the CPU power management is set to maximum performance and Turbo Boost is Enabled. | |
Number of Cores Per Processor | All | Controls the number of enabled cores in each processor. Under certain circumstances, limited performance improvements to Intel Turbo Boost Technology and potentially larger shared caches may benefit some workloads. Most computing environments tend to benefit more from a larger number of processing cores. Disabling cores to gain nominal performance enhancements must be carefully weighed before changing this setting from the default. Number of Cores per Processor means how many COREs (supported by the specific CPU SKU) can be enabled | |
Hardware Prefetcher | Enabled | When enabled, the processor can prefetch extra cache lines for every memory request. This setting can affect performance that is based on the application and workloads running on the system and memory bandwidth utilization. | |
DCU Streamer Prefetcher | Enabled | Enable or disable the Data Cache Unit (DCU) streamer prefetcher. This setting can affect performance that is based on the application and workloads running on the system. This setting is recommended for high performance computing applications. | |
DCU IP Prefetcher | Enabled | Enable or disable the Data Cache Unit (DCU) IP prefetcher. This setting can affect performance that is based on the application and workloads running on the system. This setting is recommended for high performance computing applications. | |
x2APIC | Enabled | Enable or disable the X2APIC mode. Compared to the traditional xAPIC architecture, X2APIC extends the processor addressability and enhances the performance of interrupt delivery. |
BIOS Attribute Name | Default Setting |
Adjacent Cache Line Prefetch | Enabled |
AMP Prefetch | Disabled |
AVX ICCP Pre-Grant Level | 128 Heavy |
AVX ICCP Pre-Grant License | Disabled |
AVX P1 | Normal |
CPU Physical Address Limit | Enabled |
Dead Line LLC Alloc | Enabled |
Dell Controlled Turbo Setting | Disabled |
Directory AtoS | Disabled |
Directory Mode | Enabled |
Homeless Prefetch | Auto |
Intel SST-CP | Disabled |
Kernel DMA Protection | Disabled |
Local Machine Check Exception | Enabled |
Logical Processor Idling | Disabled |
Processor N Controlled Turbo | Disabled |
Uncore Frequency RAPL | Enabled |