Intel Core i7-3770K vs Intel Core i7-990X Comparison

The Intel Core i7-990X and the Intel Core i7-3770K represent two distinct philosophies from Intel’s early 2010s lineup. The 990X, a Gulftown-based six-core Extreme edition, leverages raw core count and a large shared cache, while the 3770K, an Ivy Bridge quad-core, relies on a newer process node and higher per-core efficiency. Benchmark data shows a clear split: the 990X dominates in multi-threaded rendering workloads, whereas the 3770K takes a decisive lead in Geekbench’s broader system-level tests. With both processors landing at the 40th percentile among all CPUs and nearly identical average benchmark scores (1713 vs 1688), the choice between them hinges entirely on the specific workload.

Where Each One Wins

The Intel Core i7-990X is the unequivocal winner in Cinebench rendering tests. Across all six Cinebench R15, R20, and R23 benchmarks, the 990X posts consistent victories with delta margins of 9.5% to 10.3%. In Cinebench R15 multicore, it scores 611 against the 3770K’s 558, a 9.5% advantage. The pattern repeats in R20 multicore (2549 vs 2327, 9.5%) and R23 multicore (6071 vs 5542, 9.5%). Even in single-core Cinebench tests, the older 990X edges ahead, with a 10.3% lead in R15 single-core (86 vs 78) and a 9.6% lead in R23 single-core (857 vs 782). This suggests the 990X’s higher base clock of 3.47 GHz and boost clock of 3.73 GHz, combined with its 12 threads, provides a tangible advantage in rendering engines that scale with both core count and raw clock speed.

The Intel Core i7-3770K wins decisively in Geekbench, which measures a broader mix of integer, floating-point, and memory operations. In Geekbench multicore, the 3770K scores 3027 against the 990X’s 2612, a 13.7% margin. The single-core gap is even more pronounced: 860 vs 556, a 35.3% advantage for the 3770K. This large single-core delta indicates that the 3770K’s Ivy Bridge architecture, built on a 22 nm process with 1,400 million transistors, delivers significantly higher instructions per clock than the older Westmere design. The 3770K’s memory bandwidth of 25.6 GB/s, paired with its dual-channel DDR3 support, likely contributes to its Geekbench performance, as does its integrated Intel HD 4000 graphics, which offloads some system-level tasks.

The workload split is stark: the 990X is purpose-built for sustained multi-threaded rendering, while the 3770K excels in mixed-use scenarios that favor per-core efficiency and memory throughput. The 990X’s six cores and 12 MB of shared L3 cache give it a structural advantage in Cinebench, where the rendering algorithm rewards additional physical cores. Conversely, the 3770K’s four cores with 8 MB of shared L3 cache, running at a higher boost clock of 3.90 GHz, prove more than adequate for Geekbench’s varied workload, where the 990X’s older architecture and lower clock speeds become a liability.

The Verdict

From the data, the Intel Core i7-990X is the correct choice for users prioritizing Cinebench-style rendering workloads. Its six wins in head-to-head benchmarks, all with margins near 9.5%, make it the superior processor for multi-threaded content creation tasks like 3D rendering and video encoding. The 990X’s 12 threads and 12 MB of shared L3 cache provide a robust foundation for heavily parallel workloads, and its consistent advantage across all Cinebench versions indicates that this performance scales with increasing render complexity.

The Intel Core i7-3770K is the better pick for general-purpose computing and mixed-use applications. Its 35.3% lead in Geekbench single-core performance is a massive gap that directly impacts everyday responsiveness, application launches, and lightly-threaded tasks like web browsing or office productivity. The 13.7% multicore lead in Geekbench further suggests that the 3770K’s architecture handles memory-intensive and latency-sensitive operations more efficiently. For a desktop user who does occasional rendering but primarily runs varied applications, the 3770K’s higher Geekbench scores and lower TDP of 77 W (vs 130 W) make it the more balanced solution.

Neither processor is a clear overall winner, as their average benchmark scores are nearly identical (1713 vs 1688, a difference of 1.5%). The 990X’s nearest rival is the AMD Ryzen 7 PRO 2700U with a delta of -0.1%, while the 3770K’s closest competitor is the Intel Core i7-5850HQ with a delta of 0%. Both CPUs sit at the 40th percentile of all CPUs, indicating they are mid-range performers in a modern context. The verdict is workload-specific: choose the 990X for pure multi-threaded rendering, choose the 3770K for everything else.

Head-to-Head Benchmarks

The largest win for the Intel Core i7-990X comes in Cinebench R15 single-core, where it scores 86 against the 3770K’s 78, a 10.3% delta. This is notable because single-core performance is typically a strength of newer architectures, yet the 990X’s higher base clock of 3.47 GHz overcomes the 3770K’s architectural advantages in this specific test. The 990X also wins Cinebench R23 single-core by 9.6% (857 vs 782), reinforcing that its clock speed advantage persists even in the latest Cinebench version.

In multi-core Cinebench tests, the 990X’s margin is consistently 9.5%. Cinebench R15 multicore shows 611 vs 558, R20 multicore shows 2549 vs 2327, and R23 multicore shows 6071 vs 5542. The uniformity of this 9.5% delta across all three Cinebench versions indicates that the 990X’s core-count advantage scales linearly with workload intensity. The 990X’s six physical cores, each with 64 KB of L1 and 256 KB of L2 cache, plus the shared 12 MB L3 cache, provide a consistent throughput advantage over the 3770K’s four cores and 8 MB L3 cache.

The Intel Core i7-3770K’s largest win is in Geekbench single-core, where it scores 860 against the 990X’s 556, a 35.3% delta. This is the single biggest performance gap in the entire head-to-head comparison. The 3770K’s 22 nm Ivy Bridge architecture, with 1,400 million transistors on a 160 mm² die, delivers far superior per-core performance compared to the 990X’s 32 nm Westmere design with 1,170 million transistors on a 239 mm² die. The 3770K also wins Geekbench multicore by 13.7% (3027 vs 2612), demonstrating that even with two fewer cores, its architectural efficiency more than compensates.

The Geekbench results are particularly telling because they include memory and system-level tests. The 3770K’s memory bandwidth of 25.6 GB/s, supported by dual-channel DDR3, is a listed specification that likely contributes to its higher scores. The 990X supports triple-channel memory but has no listed bandwidth figure, suggesting its memory subsystem is less optimized for the varied Geekbench workload. This divergence between Cinebench and Geekbench results highlights that benchmark choice fundamentally determines which processor appears superior.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Core i7-990X has 6 cores and 12 threads, while the Intel Core i7-3770K has 4 cores and 8 threads. The 990X’s additional cores and threads are the primary reason for its Cinebench multicore wins.

Q: How much faster is the 3770K in Geekbench single-core?

A: The 3770K scores 860 in Geekbench single-core, which is 35.3% higher than the 990X’s score of 556. This is the largest performance gap between the two processors in any benchmark.

Q: Does the 990X win any single-core benchmark?

A: Yes, the 990X wins all six Cinebench tests, including single-core variants. In Cinebench R15 single-core, it scores 86 vs 78 (10.3% higher), and in R23 single-core, it scores 857 vs 782 (9.6% higher).

Q: What is the average benchmark score difference between the two?

A: The 990X has an average benchmark score of 1713, while the 3770K averages 1688. This is a 1.5% difference, indicating they are statistically similar performers overall.

Q: Which processor has a lower TDP?

A: The Intel Core i7-3770K has a TDP of 77 W, compared to the 990X’s 130 W. This makes the 3770K significantly more power-efficient, though this specification does not directly impact benchmark scores.

Q: Do both processors support ECC memory?

A: No, neither the 990X nor the 3770K supports ECC memory. Both list ECC memory as false in their specifications.

Architecture Differences

The architectural divide between these two processors is substantial, explaining their divergent benchmark behavior. The Intel Core i7-990X is built on the Westmere architecture, specifically the Gulftown codename, using a 32 nm process node. It integrates 1,170 million transistors on a 239 mm² die, manufactured by Intel. Its cache hierarchy consists of 64 KB of L1 cache per core, 256 KB of L2 cache per core, and a shared 12 MB L3 cache. The 990X supports DDR3 memory via a triple-channel memory bus, though no specific bandwidth figure is listed. It operates on the Intel Socket 1366 platform and provides PCIe Gen 2 connectivity. The 990X has no integrated graphics, relying entirely on a discrete GPU.

The Intel Core i7-3770K uses the Ivy Bridge architecture, also from Intel, but on a more advanced 22 nm process node. It packs 1,400 million transistors into a smaller 160 mm² die, demonstrating a higher transistor density. The 3770K’s cache structure is smaller: 64 KB L1 per core, 256 KB L2 per core, and 8 MB shared L3. It supports DDR3 memory through a dual-channel memory bus with a listed bandwidth of 25.6 GB/s. The 3770K uses the Intel Socket 1155 platform and features PCIe Gen 3 with 16 lanes from the CPU. Critically, it includes integrated Intel HD 4000 graphics, which the 990X lacks entirely.

The clock speeds also differ, with the 990X running at 3.47 GHz base and 3.73 GHz boost, while the 3770K runs at 3.50 GHz base and 3.90 GHz boost. Both have unlocked multipliers for overclocking, and both are end-of-life products. The 3770K has a listed launch MSRP of $313. The 990X’s release date is February 2011, while the 3770K arrived later in April 2012. The 990X’s larger L3 cache (12 MB vs 8 MB) and six-core design explain its Cinebench dominance, while the 3770K’s newer process node, higher boost clock, and integrated graphics contribute to its Geekbench superiority. The 3770K’s memory bandwidth advantage (25.6 GB/s) and PCIe Gen 3 support further differentiate it from the older 990X’s triple-channel memory and PCIe Gen 2. These architectural differences—process node, core count, cache size, and platform features—are the root causes of the benchmark results observed.