Intel Core i5-1345UE vs Intel Core i7-5820K Comparison

The Verdict

The recorded benchmark data is unambiguous: the Intel Core i5-1345UE is the faster processor in every single measured test, winning all six head-to-head comparisons. The i7-5820K, despite its older desktop pedigree and higher TDP, cannot match the newer mobile chip in any Cinebench workload. The i5-1345UE leads by margins between 11.7% and 11.9% across all tests, which is a consistent and decisive gap. The i7-5820K does retain one structural advantage: a quad-channel memory bus with 68.3 GB/s bandwidth, which the i5-1345UE cannot match, but this does not translate into any benchmark victory. For users choosing between these two, the i5-1345UE is the correct pick for raw compute performance, especially in single-threaded and multi-threaded Cinebench workloads. The i7-5820K remains relevant only for systems that require the older LGA 2011-3 platform, quad-channel DDR4 memory, or the unlocked multiplier for overclocking, as those features are absent from the i5-1345UE.

The average benchmark scores reinforce this conclusion. The i5-1345UE posts an average score of 2698, placing it at the 50th percentile of all CPUs in the database, while the i7-5820K averages 2642, sitting at the 49th percentile. These percentile positions are nearly identical, but the i5-1345UE achieves its position with far lower power consumption and a much newer architecture. The i7-5820K's nearest rivals, such as the Intel Xeon E-2274G at 2643 and the Intel Core i9-8950HK at 2641, are all within 0.2% of its average score, confirming that it is firmly anchored in the same performance tier. The i5-1345UE, meanwhile, trades blows with the Intel Core i7-8700T at 2701 (a 0.1% delta) and the Intel Core i7-1185G7E at 2703 (a 0.2% delta), which are newer or more efficient designs.

The verdict is straightforward: if the workload is Cinebench-style rendering or general compute, the i5-1345UE is the better chip. The i7-5820K should only be selected when the platform itself dictates the choice, such as existing LGA 2011-3 motherboards or the need for quad-channel memory capacity. The data does not support any other conclusion.

Architecture Differences

The two processors come from different eras and design philosophies. The Intel Core i5-1345UE is built on Raptor Lake, specifically the Raptor Lake-U codename, and uses a 10 nm process node from Intel. It is a mobile segment chip with a base clock of 1400.00 MHz and a boost clock of 4.60 GHz, housed in the Intel BGA 1744 socket. Its TDP is rated at 15 watts, which is exceptionally low for the performance it delivers. The i5-1345UE features 10 cores and 12 threads, a configuration that relies on the hybrid architecture typical of Raptor Lake-U parts.

The Intel Core i7-5820K, in contrast, is a Haswell-E desktop processor from 2014, built on Intel's 22 nm process node. It has 6 cores and 12 threads, with a base clock of 3.30 GHz and a boost clock of 3.60 GHz. Its TDP is 140 watts, nearly ten times that of the i5-1345UE, and it uses the Intel Socket 2011-3 platform. The i7-5820K has an unlocked multiplier, allowing overclocking, while the i5-1345UE does not. The transistor count for the i7-5820K is listed at 2,600 million, with a die size of 356 mm². The i5-1345UE has no listed transistor or die size data in the database.

Cache configurations differ substantially. The i5-1345UE has 80 KB of L1 per core, 1.25 MB of L2 per core, and 12 MB of shared L3. The i7-5820K has 64 KB of L1 per core, 256 KB of L2 per core, and a larger 15 MB of shared L3. Despite the i7-5820K having more L3, the newer i5-1345UE still wins every benchmark, indicating that raw cache capacity is not the deciding factor.

Memory support also diverges. The i5-1345UE supports both DDR4 and DDR5 across a dual-channel memory bus, while the i7-5820K supports only DDR4 but over a quad-channel bus with a rated memory bandwidth of 68.3 GB/s. Neither chip supports ECC memory. The i5-1345UE carries integrated Iris Xe Graphics with 80 execution units, whereas the i7-5820K has no integrated graphics at all. PCIe connectivity differs as well: the i5-1345UE provides Gen 4 with 8 CPU lanes, while the i7-5820K provides Gen 3 with 28 CPU lanes.

The production status tells the rest of the story. The i5-1345UE is Active, released on 2023-01-03, while the i7-5820K is End-of-life, released on 2014-08-31. The i7-5820K has a part number of SR20S; the i5-1345UE has no listed part number.

Where Each One Wins

The i5-1345UE wins in every category that the benchmark suite covers. In Cinebench R15 multicore, it scores 940 against 841, an 11.8% lead. In Cinebench R15 singlecore, it scores 132 against 118, an 11.9% lead. The pattern holds across R20 and R23, with the i5-1345UE leading by 11.7% in both multicore and singlecore variants of each test. This is not a case of one chip winning in multithreaded and the other in single-threaded; the i5-1345UE dominates both.

For users who prioritize single-threaded responsiveness, such as everyday desktop tasks, the i5-1345UE is clearly superior. Its boost clock of 4.60 GHz, combined with the newer Raptor Lake architecture, gives it a strong advantage in lightly threaded workloads. The i7-5820K's boost clock of 3.60 GHz is simply too low to compete, and its older Haswell cores cannot match the per-clock efficiency of Raptor Lake.

For heavily threaded workloads, the i5-1345UE also wins, despite having only 10 cores and 12 threads versus the i7-5820K's 6 cores and 12 threads. The extra cores, higher boost clock, and architectural improvements outweigh the i7-5820K's larger L3 cache and quad-channel memory. The i7-5820K's only theoretical advantage is memory bandwidth, which the benchmarks show does not translate into a Cinebench win.

The i7-5820K's niche is not performance, but platform features. It offers quad-channel DDR4 memory, 28 PCIe Gen 3 lanes, and an unlocked multiplier, none of which are present on the i5-1345UE. Users who need those specific capabilities, or who are already invested in the LGA 2011-3 platform, may still choose it. But on the basis of the recorded benchmark data, the i5-1345UE is the winner everywhere that matters for compute.

FAQ

Q: Which processor has the higher average benchmark score?

A: The Intel Core i5-1345UE has an average benchmark score of 2698, while the Intel Core i7-5820K scores 2642. The i5-1345UE also sits at the 50th percentile of all CPUs, one point above the i7-5820K's 49th percentile.

Q: How large is the performance gap in Cinebench R23?

A: In Cinebench R23 multicore, the i5-1345UE scores 9329 versus the i7-5820K's 8354, a lead of 11.7%. In singlecore, the i5-1345UE scores 1317 versus 1179, also an 11.7% lead.

Q: Does the i7-5820K have any benchmark wins at all?

A: No. The head-to-head comparison shows 6 wins for the Intel Core i5-1345UE and 0 wins for the Intel Core i7-5820K across all six Cinebench tests.

Q: What memory features does the i7-5820K offer that the i5-1345UE does not?

A: The i7-5820K supports quad-channel DDR4 memory with a rated bandwidth of 68.3 GB/s. The i5-1345UE supports dual-channel DDR4 and DDR5, but has no listed memory bandwidth figure.

Q: Is the i7-5820K still in production?

A: No, the i7-5820K is marked as End-of-life, while the i5-1345UE is Active.

Q: Does either processor include integrated graphics?

A: The i5-1345UE includes Iris Xe Graphics with 80 execution units. The i7-5820K has no integrated graphics.

Head-to-Head Benchmarks

The head-to-head data is remarkably consistent. Across six Cinebench tests, the Intel Core i5-1345UE wins every time with a delta percentage between 11.7% and 11.9%. The largest margin is in Cinebench R15 singlecore, where the i5-1345UE scores 132 against the i7-5820K's 118, an 11.9% advantage. The smallest margins, at 11.7%, appear in Cinebench R20 multicore (3918 versus 3508), Cinebench R20 singlecore (553 versus 495), Cinebench R23 multicore (9329 versus 8354), and Cinebench R23 singlecore (1317 versus 1179).

Cinebench R15 multicore shows the i5-1345UE at 940 versus 841, an 11.8% lead. This pattern suggests that the i5-1345UE's advantage is not workload-specific but architectural. The i7-5820K cannot close the gap in any scenario, whether the test is single-threaded or multi-threaded, older or newer. The i5-1345UE also has the benefit of a much higher boost clock (4.60 GHz versus 3.60 GHz) and a newer 10 nm process, which likely explains the consistent single-threaded advantage. In multi-threaded tests, the i5-1345UE's 10 cores and 12 threads outpace the i7-5820K's 6 cores and 12 threads, despite the latter's larger 15 MB L3 cache and quad-channel memory.

The i7-5820K does have a Geekbench multicore score of 5464 and a singlecore score of 1174 listed in its benchmark history, but no Geekbench results are recorded for the i5-1345UE in the head-to-head comparison. The six Cinebench tests are the only direct comparisons available, and the i5-1345UE wins all of them. The i7-5820K's nearest rivals in the database, the Intel Xeon E-2274G at 2643 and the Intel Core i9-8950HK at 2641, are essentially tied with it, confirming that its performance level is well below the i5-1345UE's tier.

Specification Differences

The two processors differ in nearly every specification that the database records. The Intel Core i5-1345UE has 10 cores and 12 threads, while the Intel Core i7-5820K has 6 cores and 12 threads. Base clocks are 1400.00 MHz for the i5-1345UE and 3.30 GHz for the i7-5820K, while boost clocks are 4.60 GHz and 3.60 GHz, respectively. TDP is the starkest difference: 15 watts for the i5-1345UE versus 140 watts for the i7-5820K.

The socket and platform differ completely: Intel BGA 1744 for the i5-1345UE, Intel Socket 2011-3 for the i7-5820K. The architecture is Raptor Lake (Raptor Lake-U) versus Haswell (Haswell-E). The process node is 10 nm for the i5-1345UE and 22 nm for the i7-5820K. The i7-5820K has a listed transistor count of 2,600 million and a die size of 356 mm²; the i5-1345UE has no values for either field.

Cache hierarchies are different in size and organization. The i5-1345UE has 80 KB of L1 per core and 1.25 MB of L2 per core, with 12 MB of shared L3. The i7-5820K has 64 KB of L1 per core and 256 KB of L2 per core, with 15 MB of shared L3. Memory support: the i5-1345UE supports DDR4 and DDR5 on a dual-channel bus, while the i7-5820K supports only DDR4 on a quad-channel bus with 68.3 GB/s bandwidth. Neither supports ECC memory.

PCIe connectivity: the i5-1345UE provides Gen 4 with 8 CPU lanes, the i7-5820K provides Gen 3 with 28 CPU lanes. The i5-1345UE has integrated Iris Xe Graphics with 80 execution units; the i7-5820K has none. The i5-1345UE has a locked multiplier, while the i7-5820K is multiplier-unlocked. The i5-1345UE is a mobile segment chip, Active and released 2023-01-03. The i7-5820K is a desktop segment chip, End-of-life and released 2014-08-31. The i7-5820K has the part number SR20S; the i5-1345UE has none listed. Neither processor has a launch MSRP recorded in the database.