Intel Core i3-1215U vs Intel Core i7-7700K Comparison

Where Each One Wins

The Intel Core i7-7700K takes the majority of benchmark wins in this comparison, recording 12 wins against 7 for the Intel Core i3-1215U. The i7-7700K dominates heavily in rendering workloads and memory-sensitive tasks. In Cinebench R15, R20, and R23, both multi-core and single-core tests show the i7-7700K consistently ahead by roughly 23%. That pattern extends to Geekbench multi-core, where the i7-7700K leads by 23.6%, and to data compression, where it is 17.3% faster. The i7-7700K also shows strong advantages in extended instruction performance, physics simulation, and random string sorting, with leads of 30.2%, 12.3%, and 31.9%, respectively.

The Intel Core i3-1215U, however, wins in several math-heavy and security-related workloads. It is 52.5% faster in data encryption, a very large margin, and leads by 26.2% in floating point math. It also wins integer math by 14%, multithread by 8.1%, and single-thread by 15.8%. The find prime numbers test is nearly a tie, with the i3-1215U ahead by just 3.1%. These wins point to a processor that handles arithmetic throughput and single-threaded efficiency better than the older desktop part, despite losing in most content-creation tests.

The split is clear: the i7-7700K is the stronger CPU for rendering, compression, and physics, while the i3-1215U is better for encryption, math, and general single-threaded responsiveness. Both processors land at nearly the same overall percentile, with the i7-7700K at 68 and the i3-1215U at 67, so the average benchmark score difference is small. The i7-7700K has an average benchmark score of 13291 against 12604 for the i3-1215U, a gap of roughly 5.4%. That small overall difference masks very different workload strengths.

Architecture Differences

The two processors come from different eras and design philosophies. The Intel Core i7-7700K is a desktop part built on Kaby Lake architecture, manufactured on Intel's 14 nm process. It has 4 cores and 8 threads, with a base clock of 4.20 GHz and a boost clock of 4.50 GHz. The i3-1215U is a mobile processor using Alder Lake-U architecture on a 10 nm process, with 6 cores and 8 threads. Its base clock is listed at 1200.00 MHz, which is likely a low base for efficiency, and its boost clock reaches 4.40 GHz.

Cache structures differ significantly. The i7-7700K has 64 KB of L1 cache per core, 256 KB of L2 per core, and 8 MB of shared L3. The i3-1215U has 80 KB of L1 per core, 1.25 MB of L2 per core, and 10 MB of shared L3. The larger L2 and L3 on the i3-1215U likely contribute to its wins in math and encryption, while the i7-7700K's older architecture compensates with higher clock speeds in many tests.

Memory support also separates them. The i7-7700K supports DDR4 memory only, with dual-channel bandwidth of 38.4 GB/s. The i3-1215U supports both DDR4 and DDR5, also dual-channel, but the database does not list a bandwidth figure for it. The i7-7700K uses PCIe Gen 3 with 16 lanes from the CPU, while the i3-1215U uses PCIe Gen 4 with 20 lanes. That newer PCIe standard and more lanes give the mobile chip better I/O expansion capability.

The integrated graphics differ: the i7-7700K has HD 630 while the i3-1215U has UHD Graphics 64EU. The i3-1215U is also a mobile part on socket BGA 1744, whereas the i7-7700K uses desktop socket 1151. The i7-7700K has an unlocked multiplier for overclocking, while the i3-1215U is locked. The i7-7700K has a TDP of 91 watts, reflecting its desktop power envelope, while the i3-1215U is rated at 15 watts, a fraction of that. The i3-1215U was released in early 2022, while the i7-7700K came from early 2017. Both are listed as active production parts.

Head-to-Head Benchmarks

The most decisive wins for the i7-7700K appear across the Cinebench family. In Cinebench R15 multi-core, it scores 825 against 669, a 23.3% lead. Single-core R15 shows 116 against 94, a 23.4% lead. Cinebench R20 repeats the pattern: multi-core 3439 versus 2790, single-core 485 versus 393, both at 23.3% and 23.4% deltas. Cinebench R23 continues with 8189 versus 6644 in multi-core and 1156 versus 938 in single-core, deltas of 23.3% and 23.2%. Geekbench multi-core gives the i7-7700K a 5395 to 4365 win, a 23.6% margin, while single-core Geekbench is much closer at 1547 versus 1485, only 4.2% in favor of the i7-7700K.

The i7-7700K also wins in PassMark data compression, scoring 136852 against 116705, a 17.3% margin. Extended instructions show 8943 versus 6868, a 30.2% lead. Physics simulation favors the i7-7700K at 655 against 583, a 12.3% lead. Random string sorting is the largest win for the i7-7700K at 17208 versus 13046, a 31.9% gap.

The i3-1215U's biggest win is in data encryption, where it scores 7041 against 3343, leading by 52.5%. Floating point math goes to the i3-1215U at 25379 versus 18741, a 26.2% margin. Integer math shows 35534 versus 30553, a 14% lead. PassMark multithread favors the i3-1215U at 10472 versus 9627, an 8.1% margin. Single-thread performance also belongs to the i3-1215U, with 3218 against 2708, a 15.8% lead. Find prime numbers is nearly even, 32 versus 31, a 3.1% edge for the i3-1215U.

These numbers reveal that the i7-7700K's wins are concentrated in tests that rely on memory bandwidth and cache-efficient workloads, while the i3-1215U excels in raw arithmetic and cryptographic tasks. The i3-1215U's single-thread lead is notable, given that the i7-7700K has a higher boost clock. The i3-1215U's newer architecture likely explains this advantage.

FAQ

Q: Which processor is faster in Cinebench R23 multi-core?

A: The Intel Core i7-7700K scores 8189 versus 6644 for the Intel Core i3-1215U, a 23.3% advantage.

Q: Does the i3-1215U win any single benchmark by a large margin?

A: Yes, the i3-1215U leads by 52.5% in PassMark data encryption, scoring 7041 against 3343.

Q: How do the two compare in overall average benchmark score?

A: The i7-7700K has an average benchmark score of 13291, while the i3-1215U averages 12604. The i7-7700K sits at the 68th percentile of all CPUs, and the i3-1215U at the 67th.

Q: What is the core and thread count for each?

A: The i7-7700K has 4 cores and 8 threads. The i3-1215U has 6 cores and 8 threads.

Q: Which processor has a higher single-thread PassMark score?

A: The i3-1215U scores 3218 in PassMark single-thread, which is 15.8% higher than the i7-7700K's 2708.

Q: Are both processors still in active production?

A: Yes, the database lists both the i7-7700K and the i3-1215U as active production parts.

Specification Differences

The two processors differ in nearly every major specification category. The i7-7700K is a desktop chip with 4 cores, while the i3-1215U is a mobile chip with 6 cores. Both have 8 threads. The i7-7700K has a base clock of 4.20 GHz and boost of 4.50 GHz; the i3-1215U has a base clock of 1200.00 MHz and boost of 4.40 GHz. TDP is 91 watts for the i7-7700K and 15 watts for the i3-1215U.

Socket types are entirely different: the i7-7700K uses Intel Socket 1151, while the i3-1215U uses Intel BGA 1744. The process node moves from 14 nm (i7-7700K) to 10 nm (i3-1215U). Cache sizes differ: the i7-7700K has 64 KB L1 per core, 256 KB L2 per core, and 8 MB L3 shared; the i3-1215U has 80 KB L1 per core, 1.25 MB L2 per core, and 10 MB L3 shared.

Memory support diverges: the i7-7700K supports DDR4 only, with 38.4 GB/s bandwidth, while the i3-1215U supports DDR4 and DDR5, with no listed bandwidth. PCIe generation and lanes differ: Gen 3 with 16 lanes for the i7-7700K, Gen 4 with 20 lanes for the i3-1215U. Integrated graphics go from HD 630 on the i7-7700K to UHD Graphics 64EU on the i3-1215U.

The i7-7700K has an unlocked multiplier, the i3-1215U does not. Part numbers are SR33A for the i7-7700K and SRLFU for the i3-1215U. Release dates are 2017 for the i7-7700K and 2022 for the i3-1215U. Market segments are Desktop for the i7-7700K and Mobile for the i3-1215U.

The Verdict

The data points to a clear split based on workload. For rendering, compression, and physics simulation, the Intel Core i7-7700K is the stronger choice. Its Cinebench scores are consistently about 23% higher across three generations of the test, and it leads by 17.3% in data compression and 31.9% in random string sorting. Users running CPU-bound content creation, batch processing, or database-style workloads that benefit from large, fast cache accesses will see better performance from the i7-7700K.

For encryption, math-heavy workloads, and general single-threaded tasks, the Intel Core i3-1215U is better. Its 52.5% lead in data encryption is the largest margin in the entire comparison. It also wins floating point math, integer math, and multithread tests, and its 15.8% single-thread advantage means snappier response in many everyday applications. The i3-1215U achieves this with a 15 watt TDP versus 91 watts for the i7-7700K, making it far more power-efficient.

The i7-7700K is the pick for a desktop workstation where power draw is not a concern and rendering performance matters most. The i3-1215U is the pick for a mobile system or a low-power build where encryption, math throughput, and single-thread speed are priorities. The overall average scores are close, with the i7-7700K at 13291 and the i3-1215U at 12604, but the workload split is decisive. Neither processor dominates the other completely; each wins in the areas its architecture was designed to handle.