Intel Core i3-10305 vs Intel Core i7-5775C Comparison

The Intel Core i7-5775C and Intel Core i3-10305 are both 4-core, 8-thread desktop processors from Intel, yet they represent two very different eras of the company's engineering. The data shows a clear sweep: the i3-10305 wins all six head-to-head benchmark comparisons, with a consistent performance advantage of roughly 16% across every workload tested. Despite this, the i7-5775C carries a higher launch MSRP of $366, while the i3-10305 has no listed launch MSRP, which raises immediate questions about what the older chip offers to justify its position. This analysis breaks down the benchmark results, architectural differences, and specification gaps to determine where each processor still makes sense.

Where Each One Wins

The benchmark results are unambiguous: the Intel Core i3-10305 wins every single test in the head-to-head comparison. There are zero wins for the Intel Core i7-5775C across all six Cinebench benchmarks, covering both single-core and multi-core workloads. This means the i3-10305 is the superior choice for any application that relies on raw CPU compute, from rendering in Cinebench to general productivity tasks. The i7-5775C’s only potential advantage lies in its integrated graphics, as it features Iris Pro Graphics 6200 compared to the i3-10305’s UHD Graphics 630, but no benchmark data is provided to quantify that difference. For users prioritizing CPU performance alone, the i3-10305 is the clear winner. The i7-5775C might still be relevant in legacy systems using DDR3 memory, as it supports DDR3 while the i3-10305 requires DDR4, but this is a platform consideration rather than a performance win.

Architecture Differences

These two processors are separated by over five years of Intel architecture evolution, and the data reflects this generational gap. The i7-5775C is built on the Broadwell architecture, released in 2015, while the i3-10305 uses the Comet Lake architecture, specifically Comet Lake-R, released in 2021. Both are manufactured on the same 14 nm process node at Intel’s foundry, which means the performance difference does not come from a shrink in transistor size. Instead, the i3-10305 benefits from architectural improvements within the same process generation. The i7-5775C has a die size of 182 mm², while the i3-10305’s die size is not listed in the data. The i7-5775C features 6 MB of shared L3 cache, whereas the i3-10305 has a larger 8 MB of shared L3 cache, a 2 MB difference that likely contributes to its higher performance. Both processors have identical L1 and L2 cache sizes per core: 64 KB and 256 KB respectively. The integrated graphics differ significantly, with the i7-5775C featuring Iris Pro Graphics 6200 and the i3-10305 featuring UHD Graphics 630, though no benchmark scores are provided for either. The i7-5775C also has an unlocked multiplier, while the i3-10305’s multiplier is locked, meaning the older chip offers overclocking potential that the newer one lacks.

Head-to-Head Benchmarks

The most striking pattern in the head-to-head data is the consistency of the performance gap. Across all six Cinebench tests, the i3-10305 beats the i7-5775C by a deltaPct of -16.2% to -16.4%, where the negative sign indicates the i7-5775C’s deficit. In Cinebench R15 multi-core, the i3-10305 scores 788 versus the i7-5775C’s 660, a 128-point difference. The single-core R15 test shows a similar story: 111 for the i3-10305 versus 93 for the i7-5775C. Moving to Cinebench R20, the multi-core scores are 3287 for the i3-10305 and 2750 for the i7-5775C, while single-core scores are 464 and 388 respectively. The Cinebench R23 results continue the trend: 7828 versus 6549 in multi-core and 1105 versus 924 in single-core. This uniformity suggests the performance advantage is not workload-specific but rather a fundamental throughput improvement. The i3-10305’s higher base clock of 3.80 GHz and boost clock of 4.50 GHz, compared to the i7-5775C’s 3.30 GHz base and 3.70 GHz boost, are likely the primary drivers of this consistent edge. The i3-10305 also has higher memory bandwidth at 42.7 GB/s versus 25.6 GB/s, which can impact memory-intensive workloads. The average benchmark score further confirms the gap: 2264 for the i3-10305 versus 2224 for the i7-5775C, with both processors sitting at the 47th percentile among all CPUs.

Specification Differences

The specification sheets reveal several key differences beyond the obvious performance gap. The i7-5775C uses the Intel Socket 1150, while the i3-10305 uses the Intel Socket 1200, meaning they are not interchangeable in motherboards. The i7-5775C supports DDR3 memory, whereas the i3-10305 supports DDR4, a crucial distinction for anyone building a system today. The i3-10305 has a higher base clock of 3.80 GHz and boost clock of 4.50 GHz, compared to the i7-5775C’s 3.30 GHz and 3.70 GHz. The L3 cache differs: 6 MB for the i7-5775C versus 8 MB for the i3-10305. The i7-5775C has a launch MSRP of $366, while the i3-10305 has no launch MSRP listed. The i7-5775C has an unlocked multiplier, while the i3-10305’s multiplier is locked. The i7-5775C features Iris Pro Graphics 6200, while the i3-10305 features UHD Graphics 630. The i7-5775C has a die size of 182 mm², while the i3-10305’s die size is not provided. Both processors share the same TDP of 65 watts, the same 4-core, 8-thread configuration, the same 64 KB L1 and 256 KB L2 cache per core, the same dual-channel memory bus, the same PCIe Gen 3 with 16 lanes, and both lack ECC memory support. The release dates differ significantly: the i7-5775C was released on May 14, 2015, while the i3-10305 was released on March 15, 2021.

FAQ

Q: Which processor is faster in multi-core workloads?

A: The Intel Core i3-10305 wins all multi-core benchmarks. In Cinebench R23 multi-core, it scores 7828 versus the i7-5775C’s 6549, a deltaPct of -16.3%. Similar margins appear in Cinebench R15 (788 vs 660) and R20 (3287 vs 2750).

Q: Does the i7-5775C have any advantage in single-core performance?

A: No. The i3-10305 wins all single-core tests as well. In Cinebench R23 single-core, it scores 1105 versus the i7-5775C’s 924, a deltaPct of -16.4%. The i3-10305’s higher boost clock of 4.50 GHz likely explains this edge.

Q: Can both processors be used with the same motherboard?

A: No. The i7-5775C uses Intel Socket 1150, while the i3-10305 uses Intel Socket 1200. These are incompatible platforms, requiring different motherboards.

Q: What are the memory compatibility differences?

A: The i7-5775C supports DDR3 memory with a bandwidth of 25.6 GB/s, while the i3-10305 supports DDR4 with a bandwidth of 42.7 GB/s. Both use dual-channel memory buses.

Q: Is the i7-5775C overclockable?

A: Yes. The i7-5775C has an unlocked multiplier, while the i3-10305’s multiplier is locked. This means the older chip offers manual overclocking potential that the newer one does not.

Q: How do these processors compare to their nearest rivals?

A: The i7-5775C has an average benchmark score of 2224, placing it near the Intel Core i7-8559U (2225), Intel Xeon E5-4648 v3 (2227), and Intel Xeon D-1548 (2231). The i3-10305 scores 2264, above the Intel Core i7-1068NG7 (2259), Intel Core i5-9400 (2254), Intel Core i7-10710U (2248), and AMD Ryzen 5 PRO 1500 (2246).

The Verdict

The data is unambiguous: the Intel Core i3-10305 is the superior processor in every benchmark category, winning all six head-to-head comparisons with a consistent 16% performance advantage. Anyone building a new system or upgrading for CPU-heavy tasks should choose the i3-10305, as it delivers higher multi-core and single-core scores across all Cinebench versions. The i3-10305 also supports modern DDR4 memory with higher bandwidth, which future-proofs a build. The i7-5775C’s only tangible advantages are its unlocked multiplier for overclocking and its Iris Pro Graphics 6200, but these do not compensate for the raw compute deficit. The i7-5775C might still appeal to users with existing DDR3 platforms or Socket 1150 motherboards who want a drop-in upgrade, but for any new purchase, the i3-10305 is the logical choice based strictly on the benchmark evidence. The i3-10305’s higher clocks and larger cache make it the more capable processor, and the absence of a launch MSRP for the i3-10305, contrasted with the i7-5775C’s $366 launch price, suggests the newer chip offers its performance advantage without a premium pricing signal.