Intel Xeon Phi 3120A

Power and Cooling — TDP, PSU recommendation, connector requirements

The Intel Xeon Phi 3120A carries a 300 W TDP, placing it firmly in the high-power segment of the accelerator landscape. This thermal design power is substantial for a card that relies on a dual-slot cooling solution, indicating that the cooler must move a significant amount of heat away from the 22 nm Knights Corner die. The physical dimensions of the board, 248 mm or 9.8 inches in length, are typical for a dual-slot form factor, but the absence of any display outputs means all power is directed toward compute tasks rather than video output.

For system integration, the suggested PSU rating is 700 W. This figure represents the recommended system power supply capacity, not just the card's own draw, implying that the rest of the platform—CPU, memory, storage—should be accounted for within that envelope. The power connector requirements are not specified in the available data, but the 300 W TDP and the 700 W PSU suggestion together indicate that the card demands a robust power delivery subsystem. Users pairing this accelerator with a high-core-count host processor should ensure their power supply can handle peak transient loads, as the 300 W TDP alone is a substantial baseline.

The cooling architecture is dual-slot, which is a common design for high-TDP parts, as it allows for a larger heatsink and fan assembly compared to single-slot designs. The 0 MPixel/s pixel rate and lack of display outputs further reinforce that this is a compute-oriented device, not a graphics card in the traditional sense. The 5,000 million transistors on a 720 mm² die, with a transistor density of 6.9M per mm², generate concentrated heat that the dual-slot cooler must dissipate. The end-of-life production status suggests that replacement cooling parts may become harder to source over time, making thermal maintenance a long-term consideration for existing installations.

How It Compares

The Xeon Phi 3120A occupies a unique position in the benchmark database, with a percentile rank of 50 against all GPUs, placing it exactly at the median of the performance distribution. However, the nearestRivals field is empty in the available data, which means there are no direct competitor entries with scores and deltaPct values to reference. This absence of comparative data is itself informative: the Knights Corner architecture, based on many x86 cores rather than traditional GPU shader arrays, does not slot neatly into the standard graphics card hierarchy.

Without specific rival scores, the comparison must rely on the internal specifications. The 912 shading units and 32 texture mapping units produce a texture rate of 35.20 GTexel/s, while the FP32 throughput of 2.006 TFLOPS defines its raw compute ceiling. These figures, when viewed against the 50th percentile ranking, suggest that the card lands in the middle of the pack for overall benchmark scores, though its architectural differences mean that workload-specific performance could vary widely from that median. The 6 GB GDDR5 memory and 240.0 GB/s bandwidth further position it as a mid-range compute device, though the 384-bit bus width provides a wide path for data movement.

The lack of nearest rivals also means that no direct percentage deltas can be cited. In the absence of such data, the analysis must focus on the absolute specifications and their implications. The 300 W TDP is high relative to the performance class implied by the 50th percentile, suggesting that the Xeon Phi 3120A is not power-efficient by modern standards. The 22 nm process node, while advanced for its 2012 release, is several generations behind current manufacturing, which explains the relatively modest performance per watt.

Ray Tracing and Feature Set

The Xeon Phi 3120A has no dedicated ray tracing cores and no tensor cores, according to the available specifications. This is consistent with its Knights Corner architecture, which was designed for high-performance computing and scientific workloads rather than real-time graphics rendering. The absence of these specialized units means that any ray-traced workloads would execute on the general-purpose shading units, which number 912, but without the acceleration that dedicated RT hardware provides.

The API support is notably sparse: DirectX, OpenGL, and Vulkan are all listed as null values in the fact pack. This indicates that the card does not expose traditional graphics APIs, reinforcing its role as a compute accelerator rather than a display adapter. The lack of display outputs corroborates this interpretation—there is no video signal coming from this card, so it cannot function as a primary GPU in a rendering pipeline. Instead, it would operate as a coprocessor, handling parallel compute tasks while a separate GPU manages display output.

The feature set is therefore entirely compute-focused. The FP32 performance of 2.006 TFLOPS and the texture rate of 35.20 GTexel/s represent the raw processing capabilities, but without API support or RT/tensor cores, the card is unsuitable for modern graphics workloads. The 0 MPixel/s pixel rate confirms that it performs no rasterization. For users expecting ray tracing or AI-accelerated features, this card offers no such functionality; it is a pure computational device with a specific, narrow purpose.

Who Should Consider It

Given its 50th percentile ranking and the absence of benchmark scores, the Xeon Phi 3120A is not a straightforward recommendation for typical gaming or content creation scenarios. The 6 GB GDDR5 memory, while sufficient for many workloads, is paired with a 384-bit bus and 240.0 GB/s bandwidth that are modest by current standards. For high-resolution gaming, the lack of display outputs and graphics APIs makes it entirely unsuitable—this card cannot produce an image on a monitor, and its compute-focused design means it would not accelerate DirectX or Vulkan titles.

The card's strengths lie in parallel compute tasks that can utilize its 912 shading units and 32 TMUs. The 2.006 TFLOPS FP32 throughput, while not exceptional, is adequate for certain scientific simulations, financial modeling, or data processing workloads that do not require graphics output. The 300 W TDP and 700 W PSU recommendation indicate that this is not a power-efficient choice for such tasks, but for users with existing high-wattage platforms, it could provide additional compute capacity. The end-of-life status further limits its appeal, as driver support and hardware availability are declining.

For users targeting 1080p or 1440p gaming, this card is not an option. For compute-intensive tasks that do not rely on graphics APIs, it may serve as a secondary accelerator, but the lack of modern features and the high power draw make it a difficult sell. The 22 nm process and 5,000 million transistors on a 720 mm² die are historical artifacts; current accelerators offer far better performance per watt. The 50th percentile ranking suggests that it performs on par with the median GPU in the database, but that median includes many modern cards that offer superior features and efficiency.

Benchmark Performance

The benchmark data for the Xeon Phi 3120A is sparse: the avgBenchmarkScore is 0, and the benchmarks array is empty. The percentileVsAllGpus value of 50 provides the only performance anchor, indicating that the card sits exactly at the midpoint of all GPUs in the database. This is a neutral position—neither a standout performer nor a laggard—but the lack of specific scores means that no exact deltas can be calculated against any rival.

In the absence of rival comparison data, the internal specifications offer the only performance indicators. The FP32 throughput of 2.006 TFLOPS is the primary compute metric, and the texture rate of 35.20 GTexel/s represents the card's ability to process texture data. The pixel rate of 0 MPixel/s confirms that it performs no pixel processing, which is expected for a compute accelerator. The memory bandwidth of 240.0 GB/s, derived from the 384-bit bus and 5 Gbps effective GDDR5 speed, governs how quickly data can feed the compute units.

The 50th percentile ranking suggests that, despite its age and architectural quirks, the card achieves a median level of overall performance in the database's benchmark suite. This could be due to the high core count of the Knights Corner design, which excels at certain parallel workloads even if it lags in others. However, without individual benchmark scores, it is impossible to determine which workloads favor the card and which do not. The 0 avgBenchmarkScore is likely an artifact of missing data rather than a literal zero-performance result, but it means that no quantitative comparison can be made.

Memory Subsystem

The Xeon Phi 3120A is equipped with 6 GB of GDDR5 memory, arranged on a 384-bit bus. This configuration yields a bandwidth of 240.0 GB/s, which is a moderate figure that reflects the card's 2012-era design. The memory clock is listed as 1250 MHz, with an effective data rate of 5 Gbps, which is the standard GDDR5 technique of transferring data on both clock edges.

For a compute accelerator, the memory subsystem is critical because it determines how quickly data can be fed to the 912 shading units. The 240.0 GB/s bandwidth is sufficient for many workloads, but it may become a bottleneck for tasks that require frequent large data transfers. The 6 GB capacity is generous for the era, allowing substantial datasets to reside on-card without frequent host-side transfers. The 384-bit bus width is wide, which helps sustain the bandwidth even at the modest 1250 MHz clock speed.

At high resolutions or with large datasets, the memory bandwidth becomes the limiting factor. The 240.0 GB/s figure is roughly on par with mid-range graphics cards from the same period, but it is well below the 500+ GB/s seen in modern high-end GPUs. For the Xeon Phi 3120A, the memory subsystem is adequate for its intended compute role, but it does not offer the headroom required for memory-intensive modern workloads. The 5 Gbps effective speed, while standard for GDDR5, is slow by today's standards, where 14-20 Gbps is common. This means that the card's performance is constrained not just by its compute units but also by the speed at which it can access data.