Intel Core i7-7820X vs Intel Core i9-9900 Comparison

Head-to-Head Benchmarks

The benchmark data presents a clear split between these two eight-core processors. The Intel Core i7-7820X wins six of the eight head-to-head comparisons, while the Intel Core i9-9900 takes the remaining two. The margins, however, tell a more nuanced story about where each chip excels.

In the Cinebench suite, the Core i7-7820X is consistently ahead. In Cinebench R15 multicore, it scores 1469 against the Core i9-9900's 1361, a 7.9% advantage. The single-core result in the same test shows 207 versus 192, a 7.8% lead. This pattern repeats across every Cinebench version recorded. Cinebench R20 multicore delivers 6121 for the i7-7820X versus 5673 for the i9-9900, again a 7.9% delta. The single-core R20 result is 863 against 800, also 7.9%. Cinebench R23 continues the trend: the i7-7820X posts 14576 multicore and 2057 single-core, while the i9-9900 manages 13509 and 1907 respectively. Each of those four comparisons shows the same 7.9% gap.

The consistency of that 7.9% margin across R15, R20, and R23 is notable. It suggests the performance difference in rendering workloads is structural rather than workload-specific. The i7-7820X simply executes Cinebench's rendering tasks faster, whether the workload is heavily threaded or limited to a single core.

Geekbench flips the script. The Core i9-9900 wins the multicore test with 8175 against 7855, a 3.9% advantage. The single-core gap is much larger: 1687 versus 1422, a 15.7% lead for the i9-9900. This is the most dramatic difference in the entire comparison. The i9-9900's single-core Geekbench score is substantially higher, indicating a major advantage in latency-sensitive, lightly threaded applications.

Looking at the broader database context, the i7-7820X holds a 58th percentile ranking among all CPUs with an average benchmark score of 4321. Its nearest rivals include the AMD Ryzen 7 PRO 5750G at 4296 (0.6% behind), the AMD EPYC 7232P at 4354 (0.8% ahead), the Intel Xeon E5-4669 v3 at 4285 (0.8% behind), and the Intel Xeon W-2140B at 4272 (1.1% behind). The i9-9900 sits at the 57th percentile with an average score of 4163. Its nearest rivals are the Intel Core i5-11500H at 4187 (0.6% ahead), the AMD Ryzen 9 5980HS at 4121 (1% behind), the AMD Ryzen 7 PRO 2700X at 4114 (1.2% behind), and the Intel Core i5-12500T at 4216 (1.3% ahead). Both processors sit in a dense pack of comparable performers, but the i7-7820X holds a slightly higher average score overall.

The Verdict

The data points to two different usage profiles. The Intel Core i7-7820X is the stronger choice for rendering workloads. Every Cinebench test, from R15 to R23, in both single-core and multicore forms, shows it ahead by roughly 7.9%. If the workload is built around Cinebench-style rendering, the i7-7820X is the clear winner.

The Intel Core i9-9900 is the better option for Geekbench-style tasks. Its single-core score of 1687 is 15.7% higher than the i7-7820X's 1422, and its multicore score of 8175 beats 7855 by 3.9%. Applications that resemble Geekbench's workload mix will favor the i9-9900, especially those sensitive to single-thread performance.

The i7-7820X also holds a slightly higher average benchmark score across the database: 4321 versus 4163. That is roughly a 3.8% difference in overall average, reinforcing the i7-7820X's position as the marginally faster processor on aggregate, despite the i9-9900's wins in Geekbench.

Users should choose based on workload. Rendering-heavy tasks point to the i7-7820X. Single-threaded, Geekbench-like applications point to the i9-9900. The i7-7820X also offers a higher percentile ranking at 58 versus 57, though that difference is small.

Architecture Differences

The two processors come from different architectural lineages. The Core i7-7820X uses the Skylake architecture with the Skylake-X codename, part of the Core i7 X-Series 7th Generation. The Core i9-9900 uses the Coffee Lake architecture with the Coffee Lake-R codename, part of the Core i9 Coffee Lake Refresh generation.

Both are built on Intel's 14 nm process node and manufactured by Intel. The die size differs: the i9-9900 has a die size of 180.3 mm², while the i7-7820X has no recorded die size in the database.

Cache layouts are substantially different. Both have 64 KB of L1 cache per core. The L2 cache differs: the i7-7820X has 1 MB per core, while the i9-9900 has 256 KB per core. The L3 cache favors the i9-9900 with 16 MB shared, against 11 MB shared for the i7-7820X. Neither supports 3D V-Cache.

Memory architecture is another major divergence. The i7-7820X supports quad-channel DDR4 memory with a bandwidth of 85.3 GB/s. The i9-9900 supports dual-channel DDR4 with a bandwidth of 42.7 GB/s. That is exactly double the theoretical memory bandwidth for the i7-7820X.

PCI Express capabilities also differ. The i7-7820X provides Gen 3 with 28 lanes (CPU only), while the i9-9900 provides Gen 3 with 16 lanes (CPU only). The i7-7820X offers more PCIe lanes for expansion.

The i7-7820X has no integrated graphics. The i9-9900 includes UHD Graphics 630. Neither supports ECC memory. The i7-7820X has an unlocked multiplier, while the i9-9900's multiplier is locked.

Specification Differences

The two chips differ across several key specifications. Core and thread counts are identical at 8 cores and 16 threads.

Clock speeds favor different chips in different ways. The i7-7820X has a base clock of 3.60 GHz, higher than the i9-9900's 3.10 GHz. The boost clock favors the i9-9900 at 5.00 GHz against 4.50 GHz for the i7-7820X.

Thermal design power differs significantly. The i7-7820X is rated at 140 W TDP, while the i9-9900 is rated at 65 W TDP. That is a considerable difference in power envelope.

The sockets are incompatible. The i7-7820X uses Intel Socket 2066, while the i9-9900 uses Intel Socket 1151.

Memory channels and bandwidth differ as noted: quad-channel with 85.3 GB/s for the i7-7820X, dual-channel with 42.7 GB/s for the i9-9900.

PCIe lanes differ: 28 lanes for the i7-7820X, 16 for the i9-9900.

Release dates are different. The i7-7820X was released on 2017-06-25, while the i9-9900 was released on 2019-04-22. Both are end-of-life products.

The i7-7820X has a launch MSRP of $599. The i9-9900 has a launch MSRP of $423.

Part numbers distinguish the two: SR3L5 for the i7-7820X, SRG18 for the i9-9900.

FAQ

Q: Which processor has the higher boost clock?

A: The Intel Core i9-9900 has a boost clock of 5.00 GHz, while the Intel Core i7-7820X boosts to 4.50 GHz.

Q: Which processor has higher memory bandwidth?

A: The Intel Core i7-7820X has a memory bandwidth of 85.3 GB/s via quad-channel DDR4, double the 42.7 GB/s of the dual-channel Core i9-9900.

Q: Which processor wins more head-to-head benchmarks?

A: The Intel Core i7-7820X wins six of the eight recorded head-to-head comparisons, losing only the Geekbench multicore and single-core tests.

Q: What is the single-core Geekbench margin between the two?

A: The Intel Core i9-9900 scores 1687 in Geekbench single-core, which is 15.7% higher than the Core i7-7820X's 1422.

Q: Do both processors support ECC memory?

A: No, neither the Intel Core i7-7820X nor the Intel Core i9-9900 supports ECC memory.

Q: Which processor has integrated graphics?

A: Only the Intel Core i9-9900 includes integrated graphics, specifically UHD Graphics 630. The Intel Core i7-7820X has no integrated graphics.

Where Each One Wins

The Intel Core i7-7820X wins in rendering workloads, as measured by the Cinebench suite. It leads by 7.9% in Cinebench R15 multicore, R15 single-core, R20 multicore, R20 single-core, R23 multicore, and R23 single-core. This consistency across three Cinebench versions makes it the reliable choice for rendering tasks. The i7-7820X also wins on aggregate average benchmark score, 4321 versus 4163, and holds a higher percentile ranking at 58 versus 57.

The i7-7820X also wins on platform capabilities. It offers quad-channel memory with 85.3 GB/s bandwidth, 28 PCIe Gen 3 lanes, and a higher base clock of 3.60 GHz. It has an unlocked multiplier, making it suitable for overclocking scenarios. Its L2 cache is larger at 1 MB per core, and its TDP of 140 W reflects a more power-hungry but potentially more capable platform design.

The Intel Core i9-9900 wins in Geekbench-style workloads. Its single-core score of 1687 is 15.7% ahead, and its multicore score of 8175 is 3.9% ahead. The i9-9900 also has a higher boost clock of 5.00 GHz, more L3 cache at 16 MB shared, and a much lower TDP of 65 W. It includes integrated graphics, which the i7-7820X lacks entirely.

The i9-9900 is the choice for users prioritizing single-thread performance and power efficiency. The i7-7820X is the choice for users prioritizing rendering throughput, memory bandwidth, and PCIe expansion. Both are end-of-life desktop processors, but their strengths remain clearly separated in the recorded data.