Intel Core 3 305 vs Intel Core Ultra 7 265HX Comparison

Head-to-Head Benchmarks

The benchmark data records a decisive sweep: the Intel Core Ultra 7 265HX wins all 17 head-to-head comparisons against the Intel Core 3 305. The largest margins appear in integer and floating-point workloads. In PassMark integer math, the Ultra 7 scores 126,954 against 32,295, a delta of 74.6%. Floating-point math shows a similar gap, with 161,605 versus 42,284, a 73.8% advantage. These are the two biggest percentage differences in the entire comparison.

Multithreaded rendering benchmarks confirm the pattern. Cinebench R23 multicore gives the Ultra 7 a score of 40,642 compared to 13,123 for the Core 3, a 67.7% delta. Cinebench R20 multicore follows the same ratio: 17,069 versus 5,511, again 67.7%. Cinebench R15 multicore shows 4,096 against 1,322, also 67.7%. The consistency of the 67.7% delta across all three Cinebench multicore tests indicates that the performance gap scales linearly with the workload type, not with the specific benchmark version.

Single-core results tell a different story in magnitude. The Ultra 7 leads Cinebench R23 single-core with 5,737 points versus 1,852, a 67.7% delta, identical to the multicore margin. PassMark single-thread is far closer: 4,500 versus 3,977, a delta of only 11.6%. This is the narrowest gap in the entire dataset. The data suggests that the Core 3 305 holds up reasonably well in lightly threaded integer tasks, but the Ultra 7 pulls far ahead once the workload scales across its larger core count.

Data compression and encryption workloads amplify the Ultra 7's advantage. PassMark data compression shows 511,817 versus 146,857, a 71.3% delta. Data encryption delivers 39,472 versus 11,019, a 72.1% delta. Random string sorting also favors the Ultra 7 heavily: 62,458 versus 17,623, a 71.8% delta. Prime number finding shows 406 versus 115, a 71.7% delta. Extended instruction workloads record 40,741 versus 13,543, a 66.8% delta, the smallest margin outside the single-thread tests.

PassMark multithread and physics results round out the picture. The Ultra 7 scores 47,985 in PassMark multithread against 15,439, a 67.8% delta. Physics shows 2,978 versus 1,233, a 58.6% delta, the second-smallest percentage gap on the board. The overall average benchmark scores reinforce this hierarchy: the Ultra 7 averages 63,173, while the Core 3 averages 18,302. The Ultra 7 sits at the 93rd percentile of all CPUs in the database, while the Core 3 sits at the 72nd percentile.

Architecture Differences

The two processors come from different design lineages. The Core 3 305 is based on Wildcat Lake, a 3 nm Intel design, while the Ultra 7 265HX uses Arrow Lake-HX, also on a 3 nm process but fabricated by TSMC rather than Intel. The Ultra 7 belongs to the Core Ultra Series 2 family; the Core 3 has no series designation in the database.

Core and thread counts differ substantially. The Core 3 305 provides 6 cores and 6 threads, with no hyperthreading. The Ultra 7 265HX provides 20 cores and 20 threads, also without hyperthreading. That 14-core difference explains much of the multicore performance gap, though the single-core delta in Cinebench suggests architectural improvements also play a role.

Cache hierarchies are structured differently. The Core 3 305 has 192 KB of L1 cache total, 2.5 MB of L2, and 6 MB of shared L3. The Ultra 7 265HX lists 192 KB of L1 per core, 3 MB of L2 per core, and 30 MB of shared L3. The per-core L2 allocation on the Ultra 7 means its total L2 scales with the core count, reaching far beyond the Core 3's fixed 2.5 MB. The L3 difference is stark: 30 MB shared versus 6 MB shared.

Clock speeds favor the Ultra 7 in both base and boost. The Core 3 runs at 1.50 GHz base and 4.30 GHz boost. The Ultra 7 runs at 2.60 GHz base and 5.30 GHz boost. The 1.10 GHz base clock advantage and 1.00 GHz boost advantage contribute to the single-thread performance lead, though the PassMark single-thread gap of 11.6% is smaller than the raw clock difference might suggest.

Memory architecture diverges as well. The Core 3 305 supports DDR5 and LPDDR5X over a single-channel memory bus, delivering 59.7 GB/s of bandwidth. The Ultra 7 265HX supports DDR5 over a dual-channel bus, delivering 102.4 GB/s. The bandwidth difference of 42.7 GB/s (71.5% higher on the Ultra 7) matters for memory-intensive workloads like compression and encryption, where the Ultra 7's lead exceeds its core-count advantage.

PCIe connectivity differs by a full generation. The Core 3 provides Gen 4 with 6 CPU lanes. The Ultra 7 provides Gen 5 with 20 CPU lanes. The Ultra 7 also has an unlocked multiplier, while the Core 3 is locked. The integrated graphics units differ: the Core 3 uses Intel Xe3 Graphics with 1 Xe, while the Ultra 7 uses Arc Xe-LPG Graphics with 64 execution units. Both are mobile parts, and both are currently listed as Active in production status.

Transistor and die data exist only for the Ultra 7: 17,800 million transistors on a 243 mm² die. No equivalent figures are recorded for the Core 3. The sockets are incompatible: the Core 3 uses Intel BGA 1516, and the Ultra 7 uses Intel BGA 2114.

FAQ

Q: Which processor wins in single-threaded performance?

A: The Intel Core Ultra 7 265HX leads in every single-thread test recorded. Cinebench R23 single-core shows 5,737 versus 1,852, a 67.7% delta. PassMark single-thread shows 4,500 versus 3,977, an 11.6% delta.

Q: How large is the multicore performance gap?

A: The Ultra 7 leads by 67.7% in all three Cinebench multicore tests (R15, R20, R23) and by 67.8% in PassMark multithread. The largest multicore-type gap is in PassMark integer math at 74.6%.

Q: What memory bandwidth does each processor support?

A: The Core 3 305 supports single-channel memory with 59.7 GB/s bandwidth and accepts DDR5 and LPDDR5X. The Ultra 7 265HX supports dual-channel memory with 102.4 GB/s bandwidth and accepts DDR5.

Q: Do both processors use the same socket?

A: No. The Core 3 305 uses Intel BGA 1516, while the Ultra 7 265HX uses Intel BGA 2114. They are not interchangeable.

Q: Are there any benchmarks where the Core 3 305 wins?

A: No. The recorded data shows the Ultra 7 winning all 17 head-to-head comparisons. The Core 3's best relative result is PassMark single-thread, where it trails by only 11.6%.

Q: What is the difference in CPU core counts?

A: The Core 3 305 has 6 cores and 6 threads. The Ultra 7 265HX has 20 cores and 20 threads. Neither processor uses simultaneous multithreading.

Specification Differences

| Specification | Intel Core 3 305 | Intel Core Ultra 7 265HX |

|---|---|---|

| Cores | 6 | 20 |

| Threads | 6 | 20 |

| Base clock | 1.50 GHz | 2.60 GHz |

| Boost clock | 4.30 GHz | 5.30 GHz |

| TDP | 15 W | 55 W |

| Socket | Intel BGA 1516 | Intel BGA 2114 |

| Codename | Wildcat Lake | Arrow Lake-HX |

| Generation | Core 3 (Wildcat Lake) | Ultra 7 (Arrow Lake-HX) |

| Foundry | Intel | TSMC |

| Transistors | Not recorded | 17,800 million |

| Die size | Not recorded | 243 mm² |

| L1 cache | 192 KB total | 192 KB per core |

| L2 cache | 2.5 MB | 3 MB per core |

| L3 cache | 6 MB shared | 30 MB shared |

| Memory support | DDR5, LPDDR5X | DDR5 |

| Memory bus | Single-channel | Dual-channel |

| Memory bandwidth | 59.7 GB/s | 102.4 GB/s |

| PCIe | Gen 4, 6 lanes | Gen 5, 20 lanes |

| Integrated graphics | Intel Xe3 Graphics (1 Xe) | Arc Xe-LPG Graphics 64EU |

| Multiplier unlocked | No | Yes |

| Launch MSRP | $309 | Not recorded |

Both processors share the 3 nm process node, mobile market segment, Active production status, and lack of ECC memory support. The Ultra 7's launch MSRP is not recorded in the database.

The Verdict

The data draws a clear line between these two mobile processors. The Intel Core Ultra 7 265HX dominates every recorded benchmark, with margins ranging from 11.6% in PassMark single-thread to 74.6% in PassMark integer math. Its 20-core configuration, dual-channel memory at 102.4 GB/s, and 30 MB of L3 cache provide a structural advantage that the Core 3 305 cannot offset.

The Intel Core 3 305 is positioned for lighter duty. Its 6-core, 6-thread layout, single-channel memory at 59.7 GB/s, and 6 MB L3 cache place it well below the Ultra 7 in throughput-oriented work. Its 15 W TDP, versus 55 W for the Ultra 7, indicates a lower-power design suitable for systems where thermals and battery life take priority over peak performance. The Core 3's closest rivals in the database are the Intel Core i3-14100, Intel Core 5 330, Intel Core 7 360, and AMD Ryzen 5 2600E, all within 0.4% of its average score.

The Ultra 7 competes in a different tier. Its nearest rivals include the Intel Core i7-13790F, AMD Ryzen AI 7 450G, AMD Ryzen AI Embedded P185, and Intel Core Ultra 7 255HX, all within 0.7% of its average score. The 93rd percentile ranking places it among the higher-performing mobile CPUs in the database, while the Core 3's 72nd percentile reflects a more modest standing.

For single-threaded responsiveness, the gap narrows considerably. The PassMark single-thread delta of 11.6% is the only benchmark where the Core 3 comes within shouting distance. Buyers prioritizing light, fanless or low-power designs would find the Core 3's 15 W envelope attractive. Buyers needing sustained multicore throughput, fast data compression, or heavy floating-point math would choose the Ultra 7, which delivers roughly three times the average benchmark score: 63,173 versus 18,302. The recorded data offers no scenario where the Core 3 outperforms the Ultra 7, so the choice rests entirely on power constraints and workload requirements.