Intel Core 3 305 vs Intel Core Ultra 5 245K Comparison

Head-to-Head Benchmarks

The benchmark data presents a decisive sweep: the Intel Core Ultra 5 245K wins all 17 recorded head-to-head tests, with the Intel Core 3 305 trailing across every workload category. The largest single-core gap appears in Cinebench R15, where the Core Ultra 5 245K scores 322 against the Core 3 305's 186, a 42.2% advantage. That margin narrows substantially in Cinebench R23 single-core, where the Core Ultra 5 245K leads 2132 to 1852, a 13.1% difference, indicating that newer rendering workloads compress the per-thread performance gap.

Multi-threaded workloads show a far wider separation. In Cinebench R23 multi-core, the Core Ultra 5 245K registers 25066 points versus 13123 for the Core 3 305, a 47.6% deficit for the mobile chip. The older Cinebench R20 multi-core test shows a 64.1% gap, with the Core Ultra 5 245K scoring 15368 against 5511. Cinebench R15 multi-core follows the same pattern: 3850 for the Core Ultra 5 245K and 1322 for the Core 3 305, a 65.7% difference. These results confirm that the desktop part's additional cores and higher power envelope translate into roughly 1.9x to 2.9x the multi-core output depending on the test generation.

PassMark workloads reinforce the dominance. Data compression shows the Core Ultra 5 245K at 458817 points, which is 68% ahead of the Core 3 305's 146857. Integer math sees 98524 versus 32295, a 67.2% gap, while floating-point math runs 130678 against 42284, a 67.6% difference. The encryption test shows 33286 for the Core Ultra 5 245K against 11019, a 66.9% lead. Prime number finding is the most lopsided: 414 versus 115, a 72.2% advantage for the desktop chip.

The closest result in the entire matrix is PassMark single-thread, where the Core Ultra 5 245K scores 4714 versus 3977, a 15.6% gap. Physics simulation shows a 60% difference (3081 to 1233), while random string sorting lands at 55098 versus 17623, a 68% gap. Extended instructions run 37617 against 13543, a 64% difference. Across all 17 tests, the average benchmark score for the Core Ultra 5 245K is 54053, placing it in the 91st percentile of all CPUs in the database. The Core 3 305 averages 18302, sitting in the 72nd percentile.

The nearest rival data adds context. The Core 3 305's average score of 18302 sits within 0.4% of the AMD Ryzen 5 2600E (18230) and within 0.1% of the Intel Core i3-14100 (18318). It also trails the Intel Core 5 330 by 0.2% (18345) and the Intel Core 7 360 by 0.4% (18374). For the Core Ultra 5 245K, the 54053 average is 0.7% ahead of the Intel Xeon 6505P (53701), 0.8% ahead of the Intel Core i7-14700F (53620), and 1.1% ahead of the Intel Xeon Phi 7290 (53469), while falling 1.3% behind the AMD Ryzen 9 9900X3D (54762).

FAQ

Q: Which processor wins every head-to-head benchmark?

A: The Intel Core Ultra 5 245K wins all 17 recorded tests, including every Cinebench R15, R20, R23 and PassMark workload. The Core 3 305 does not win a single comparison.

Q: How large is the multi-core performance gap?

A: The Core Ultra 5 245K leads by 47.6% in Cinebench R23 multi-core, 64.1% in Cinebench R20 multi-core, and 65.7% in Cinebench R15 multi-core. PassMark multi-thread shows a 64.1% gap.

Q: Is the single-core gap smaller than the multi-core gap?

A: Yes. The narrowest single-core margin is 13.1% in Cinebench R23 (2132 vs 1852), while PassMark single-thread shows 15.6%. Older Cinebench R20 single-core shows 64.2% and R15 single-core shows 42.2%.

Q: What is the percentile ranking of each CPU in the database?

A: The Core Ultra 5 245K ranks in the 91st percentile of all CPUs, while the Core 3 305 ranks in the 72nd percentile. The average benchmark scores are 54053 and 18302 respectively.

Q: How do the two compare to their nearest rivals?

A: The Core 3 305's average score is 0.1% below the Intel Core i3-14100 and 0.4% above the AMD Ryzen 5 2600E. The Core Ultra 5 245K is 0.7% above the Intel Xeon 6505P and 1.3% below the AMD Ryzen 9 9900X3D.

Q: Which workload shows the largest percentage difference?

A: PassMark find prime numbers shows the largest gap at 72.2%, with the Core Ultra 5 245K scoring 414 against the Core 3 305's 115.

Architecture Differences

The two processors come from different Intel product lines and are built for different segments. The Core 3 305 uses the Wildcat Lake codename and belongs to the Core 3 generation. The Core Ultra 5 245K uses the Arrow Lake architecture, specifically Arrow Lake-S, and belongs to the Core Ultra Series 2 generation.

Both parts are manufactured on a 3 nm process node, but the foundries differ. The Core 3 305 is fabricated by Intel, while the Core Ultra 5 245K is fabricated by TSMC. The Core Ultra 5 245K has a documented transistor count of 17,800 million and a die size of 243 mm². The Core 3 305 does not have recorded transistor or die size data.

The Core Ultra 5 245K integrates Arc Xe-LPG Graphics with 64 execution units. The Core 3 305 integrates Intel Xe3 Graphics with 1 Xe unit. This represents a generational change in integrated graphics architecture, with the Xe3 branding on the mobile chip and the Xe-LPG branding on the desktop part.

PCIe support differs substantially. The Core Ultra 5 245K provides Gen 5 connectivity with 20 CPU lanes. The Core 3 305 provides Gen 4 with 6 CPU lanes. This reflects the desktop platform's need for high-bandwidth expansion, versus the mobile part's constrained I/O budget.

Memory architecture also diverges. The Core Ultra 5 245K uses a dual-channel memory bus with a peak bandwidth of 102.4 GB/s. The Core 3 305 uses a single-channel bus with 59.7 GB/s. The Core Ultra 5 245K supports ECC memory, while the Core 3 305 does not. Both support DDR5, but the Core 3 305 also supports LPDDR5X.

The Core Ultra 5 245K has an unlocked multiplier, allowing overclocking. The Core 3 305 has a locked multiplier. This aligns with the desktop part's positioning as an enthusiast-oriented product with user-adjustable clocks.

Socket compatibility is entirely different. The Core Ultra 5 245K uses Intel Socket 1851, a desktop socket. The Core 3 305 uses Intel BGA 1516, a ball-grid array package designed for mobile systems. The production status for both is Active.

Specification Differences

The core and thread counts are the largest specification gap. The Core Ultra 5 245K has 14 cores and 14 threads, while the Core 3 305 has 6 cores and 6 threads. Neither part uses Hyper-Threading, as thread counts equal core counts in both cases.

Clock speeds favor the desktop chip. The Core Ultra 5 245K has a base clock of 4.20 GHz and a boost clock of 5.20 GHz. The Core 3 305 has a base clock of 1.50 GHz and a boost clock of 4.30 GHz. The base clock difference of 2.70 GHz is notable, while the boost clock gap narrows to 0.90 GHz.

Thermal design power differs by a factor of more than eight. The Core Ultra 5 245K has a TDP of 125, while the Core 3 305 has a TDP of 15. This reflects the mobile chip's power efficiency priority and the desktop chip's performance headroom.

Cache configurations diverge in size and organization. The Core Ultra 5 245K has 192 KB of L1 cache per core, 3 MB of L2 cache per core, and 24 MB of shared L3 cache. The Core 3 305 has 192 KB of L1 cache, 2.5 MB of L2 cache, and 6 MB of shared L3 cache. The L3 cache difference is 18 MB.

The memory bus width and bandwidth favor the desktop part. The Core Ultra 5 245K supports dual-channel DDR5 with 102.4 GB/s bandwidth. The Core 3 305 supports single-channel DDR5 and LPDDR5X with 59.7 GB/s. ECC memory support is present only on the Core Ultra 5 245K.

PCIe generation and lane count differ. The Core Ultra 5 245K offers Gen 5 with 20 CPU lanes. The Core 3 305 offers Gen 4 with 6 CPU lanes. Integrated graphics differ as well: Arc Xe-LPG Graphics with 64EU on the Core Ultra 5 245K versus Intel Xe3 Graphics with 1 Xe on the Core 3 305.

Market segment and release dates also differ. The Core Ultra 5 245K is a desktop part released on 2024-10-23, while the Core 3 305 is a mobile part released on 2026-04-15. The launch MSRP for the Core Ultra 5 245K is $319, and the launch MSRP for the Core 3 305 is $309. The Core Ultra 5 245K has part number SRQCT, while the Core 3 305 has part number SAE3L.

The Verdict

The recorded data draws a clear separation. The Intel Core Ultra 5 245K is the stronger processor in every single benchmark, with average scores nearly three times higher (54053 versus 18302) and a 91st percentile ranking versus the 72nd percentile for the Core 3 305. Desktop users who need multi-threaded rendering performance, data compression throughput, or encryption speed will find the Core Ultra 5 245K delivers 47.6% to 72.2% more performance across those workloads.

The Core 3 305 is not without purpose. Its 15 TDP, single-channel memory, and BGA package target mobile systems where power draw and physical footprint take priority over raw compute. Its boost clock of 4.30 GHz is within 0.90 GHz of the desktop part, and the Cinebench R23 single-core margin of 13.1% shows that lightly threaded tasks on the mobile chip remain respectable. The 6 MB shared L3 cache and 59.7 GB/s bandwidth are sufficient for its intended workload class.

The benchmark data indicates the Core 3 305 competes closely with mid-range desktop parts from the previous generation. Its average score of 18302 is within 0.4% of the AMD Ryzen 5 2600E and 0.1% of the Intel Core i3-14100. That places it in the same performance tier as those older desktop chips, but with a much lower power envelope and mobile packaging.

The Core Ultra 5 245K, by contrast, sits in a higher tier. Its 54053 average score puts it above the Intel Xeon 6505P (0.7%), the Intel Core i7-14700F (0.8%), and the Intel Xeon Phi 7290 (1.1%). Only the AMD Ryzen 9 9900X3D ranks higher among its nearest rivals, by 1.3%. The 14-core count, 24 MB L3, dual-channel 102.4 GB/s memory, and Gen 5 PCIe lanes position it as a desktop workstation or high-end consumer part.

The selection between the two depends entirely on the platform. The Core Ultra 5 245K requires an LGA 1851 motherboard, supports ECC memory, and has an unlocked multiplier. The Core 3 305 is soldered to BGA 1516, cannot be overclocked, and uses single-channel memory. The data does not support any scenario where the Core 3 305 outperforms the Core Ultra 5 245K in compute; it only offers a dramatically lower power draw and a smaller physical footprint. For any workload measured in the database, the Core Ultra 5 245K is the correct choice. For portable systems where 15 TDP is mandatory, the Core 3 305 is the only one of the two that fits.