Intel Core i3-9100 vs Intel Core i5-8305G Comparison

Head-to-Head Benchmarks

The benchmark data shows a clear overall winner: the Intel Core i5-8305G takes 7 of 8 head-to-head tests, with the Intel Core i3-9100 securing only a single victory. However, the margins are not uniform, and the one loss matters for certain workloads.

In multi-core workloads, the i5-8305G consistently outpaces the i3-9100 by a narrow but repeatable margin. In Cinebench R15 multi-core, the i5-8305G scores 578 against 566 for the i3-9100, a 2.1% advantage. That same 2.1% gap appears again in Cinebench R20 multi-core (2410 vs 2361) and again in Cinebench R23 multi-core (5739 vs 5622). The pattern is remarkably stable across all three Cinebench iterations, suggesting the multi-core advantage is structural rather than workload-specific. The i5-8305G also leads in Geekbench multi-core by a larger margin: 3536 versus 3403, a 3.9% difference. This is the biggest multi-core win for the i5-8305G in the entire comparison.

Single-core results tell a slightly different story. In Cinebench R15 single-core, the i5-8305G scores 81 versus 79 for the i3-9100, a 2.5% edge. In Cinebench R20 single-core, the lead is 340 versus 333, again 2.1%. In Cinebench R23 single-core, the i5-8305G posts 810 versus 793, also 2.1%. So across all three Cinebench single-core tests, the i5-8305G wins by the same 2.1% to 2.5% margins. But in Geekbench single-core, the tables turn decisively: the i3-9100 scores 1290 against 1150 for the i5-8305G, a 10.9% advantage. This is the largest delta in the entire head-to-head set, and it flips the single-core narrative depending on which benchmark you trust.

The average benchmark score reflects the overall split. The i5-8305G averages 1831 across all recorded tests, while the i3-9100 averages 1806. That is a 1.4% overall gap, smaller than the individual multi-core deltas because the Geekbench single-core loss pulls the i5-8305G down. Both processors sit at the 42nd percentile among all CPUs in the database, meaning they occupy the same general performance tier despite the i5-8305G winning most direct comparisons.

Looking at nearest rivals, the i5-8305G sits essentially tied with the AMD Ryzen 5 4600U (1832 average, 0% delta), the Intel Xeon E5-2608L v3 (1830, 0%), and the Intel Xeon D-1537 (1830, 0.1% ahead). The i3-9100 matches up against the Intel Core i3-9320 (1808, 0.1% behind), the AMD Ryzen 5 PRO 4650U (1810, 0.2% behind), and the Intel Xeon E5-1620 v4 (1802, 0.2% ahead). Neither chip breaks out of its immediate competitive cluster.

Where Each One Wins

The i5-8305G wins every multi-threaded workload in the dataset. That includes all three Cinebench multi-core tests at 2.1% margins and Geekbench multi-core at 3.9%. If the task is rendering, video encoding, compilation, or any heavily threaded application, the i5-8305G is the stronger part. The advantage comes from its thread count: 8 threads versus 4 on the i3-9100. Even though both have 4 physical cores, the i5-8305G’s ability to process two threads per core gives it a consistent edge in parallel workloads. The data shows that edge is real but modest, never exceeding 3.9% in any multi-core test.

The i3-9100 wins only one test: Geekbench single-core, by 10.9%. This is a substantial margin, the largest of any comparison in the dataset. For lightly threaded tasks such as legacy applications, certain game engines that rely on a single primary thread, or interactive responsiveness in single-threaded productivity tools, the i3-9100 has a clear advantage. The Geekbench single-core result stands out because it contradicts the Cinebench single-core results, where the i5-8305G wins by 2.1% to 2.5%. The discrepancy suggests the two benchmarks stress different aspects of single-core performance, with Geekbench favoring the i3-9100’s higher clock speeds.

Clock speed is likely the deciding factor in that single-core loss. The i3-9100 has a base clock of 3.60 GHz and a boost clock of 4.20 GHz, while the i5-8305G runs at 2.80 GHz base and 3.80 GHz boost. The i3-9100’s boost clock is 0.40 GHz higher, and its base clock is 0.80 GHz higher. In a single-threaded test that scales directly with frequency, that advantage shows up. In the Cinebench single-core tests, the i5-8305G still wins despite the clock deficit, which indicates its architecture or cache behavior compensates. But Geekbench exposes the frequency gap.

For the average user, the split means this: choose the i5-8305G for anything that uses more than one thread, and choose the i3-9100 only for strictly single-threaded workloads where Geekbench-style performance matters more than Cinebench-style performance. The i5-8305G also has the edge in the aggregate, with a higher average benchmark score.

Architecture Differences

The two processors come from different Intel architectural families. The i5-8305G is built on Kaby Lake, specifically the Kaby Lake G variant, while the i3-9100 uses Coffee Lake, part of the Coffee Lake Refresh generation. Both are manufactured on Intel’s 14 nm process at Intel’s foundry, so the transistor-level fabrication is identical. The difference lies in the architectural implementation and feature set.

The most significant architectural divergence is the integrated graphics. The i5-8305G pairs its CPU cores with a Radeon RX Vega M GL graphics processor, a discrete-class GPU integrated into the same package. The i3-9100 uses Intel’s UHD Graphics 630. The database does not provide graphics benchmarks, so a direct performance comparison is not possible from the recorded data. However, the presence of the Radeon Vega M GL indicates the i5-8305G is designed for workloads that benefit from substantial GPU compute, such as light gaming, GPU-accelerated encoding, or general-purpose GPGPU tasks. The UHD Graphics 630 is a conventional integrated solution typical of desktop mainstream processors.

The i5-8305G is a mobile processor, as indicated by its market segment and socket. It uses the Intel BGA 2270 socket, which is a ball-grid array designed for soldered laptop installations. The i3-9100 is a desktop part using Intel Socket 1151, a land-grid array socket that allows for socketed installation and replacement. This difference has practical implications for upgrading and system design, though the database does not include performance data specific to socket type.

Cache configuration is identical between the two: 64 KB of L1 per core, 256 KB of L2 per core, and 6 MB of shared L3 cache. Both use DDR4 memory without ECC support on the i5-8305G, while the i3-9100 supports ECC memory. The i3-9100 also specifies a dual-channel memory bus with 38.4 GB/s of bandwidth, while the i5-8305G lists no memory bus or bandwidth details. The i3-9100 has 16 PCIe Gen 3 lanes from the CPU, while the i5-8305G has no PCIe specification recorded.

The i5-8305G was released on January 31, 2018, and remains in active production. The i3-9100 was released on August 31, 2018, and is now end-of-life. Both are quad-core parts, but the i5-8305G has 8 threads versus 4 on the i3-9100. Neither has an unlocked multiplier.

Specification Differences

The two processors differ in several key specifications, and the data allows a direct side-by-side comparison.

The i5-8305G has 4 cores and 8 threads, while the i3-9100 has 4 cores and 4 threads. This is the most consequential difference for multi-threaded performance. The i5-8305G runs at a base clock of 2.80 GHz and boosts to 3.80 GHz. The i3-9100 runs at 3.60 GHz base and 4.20 GHz boost. The i3-9100 is faster in both metrics, with a 0.80 GHz higher base and a 0.40 GHz higher boost.

Both processors have a TDP of 65 watts, so power consumption is identical on paper. The i5-8305G uses the Intel BGA 2270 socket, while the i3-9100 uses Intel Socket 1151. The i5-8305G is built on Kaby Lake, the i3-9100 on Coffee Lake. Both use a 14 nm process at Intel’s foundry.

The i5-8305G integrates a Radeon RX Vega M GL GPU, while the i3-9100 uses UHD Graphics 630. The i5-8305G does not support ECC memory; the i3-9100 does. The i3-9100 has a dual-channel memory bus with 38.4 GB/s bandwidth, while the i5-8305G has no memory bus or bandwidth figures recorded. The i3-9100 has 16 PCIe Gen 3 lanes, while the i5-8305G has no PCIe specification listed. The i3-9100 has a die size of 126 mm², while the i5-8305G has no die size recorded. The i3-9100 has a part number of SRCZV, while the i5-8305G has no part number listed.

The i5-8305G is in active production, while the i3-9100 is end-of-life. The i3-9100 has a launch MSRP of $122, while the i5-8305G has no launch MSRP recorded in the database.

FAQ

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

A: The Intel Core i5-8305G wins all multi-core tests in the database. It leads by 2.1% in Cinebench R15, R20, and R23 multi-core, and by 3.9% in Geekbench multi-core.

Q: Does the Intel Core i3-9100 win any benchmarks?

A: Yes, it wins Geekbench single-core with a score of 1290 versus 1150 for the i5-8305G, a 10.9% advantage. That is the only benchmark win for the i3-9100 out of 8 head-to-head tests.

Q: Why does the i3-9100 win in Geekbench single-core but lose in Cinebench single-core?

A: The i3-9100 has a higher boost clock (4.20 GHz versus 3.80 GHz) and a higher base clock (3.60 GHz versus 2.80 GHz). The Geekbench single-core test appears to reward that frequency advantage, while the Cinebench single-core tests favor the i5-8305G by 2.1% to 2.5% despite the clock deficit.

Q: Do both processors have the same number of cores?

A: Yes, both have 4 physical cores. However, the i5-8305G has 8 threads while the i3-9100 has 4 threads, meaning the i5-8305G can process two threads per core and the i3-9100 cannot.

Q: What are the cache sizes for each processor?

A: Both have identical cache configurations: 64 KB of L1 per core, 256 KB of L2 per core, and 6 MB of shared L3 cache.

Q: Which processor is still in production?

A: The i5-8305G is listed as active in production, while the i3-9100 is end-of-life.

The Verdict

The data points to the Intel Core i5-8305G as the better overall processor. It wins 7 of 8 head-to-head benchmarks, has a higher average benchmark score (1831 versus 1806), and holds a consistent 2.1% edge across all three Cinebench multi-core tests plus a 3.9% edge in Geekbench multi-core. The 8-thread configuration gives it a structural advantage in parallel workloads that the 4-thread i3-9100 cannot overcome.

The i3-9100 is the better choice only for strictly single-threaded, Geekbench-style workloads. Its 10.9% win in Geekbench single-core is the largest margin in the comparison, and its higher base and boost clocks provide a real frequency advantage. For users running applications that depend on a single thread and respond strongly to clock speed, the i3-9100 will deliver measurably better performance.

For everyone else, the i5-8305G is the safer pick. Its multi-core wins are consistent across every Cinebench iteration, and its average benchmark score is higher overall. The fact that it is still in active production while the i3-9100 is end-of-life also suggests better long-term availability for new systems.

The desktop versus mobile distinction is important. The i3-9100 uses Socket 1151 and is designed for desktop builds, while the i5-8305G uses BGA 2270 and is a mobile part. A system builder choosing between these will largely be deciding between a desktop platform and a mobile platform. Within that context, the i5-8305G offers better multi-core performance and a more capable integrated GPU (Radeon RX Vega M GL versus UHD Graphics 630), while the i3-9100 offers higher clock speeds, ECC memory support, and a documented dual-channel memory bus with 38.4 GB/s of bandwidth.

The overall verdict: choose the i5-8305G for multi-threaded computing and for systems where the integrated Radeon GPU is relevant. Choose the i3-9100 for single-threaded responsiveness, for desktop builds requiring Socket 1151, or for applications that need ECC memory support. In terms of raw aggregate performance, the i5-8305G is the stronger processor by every multi-core metric in the database.