AMD Ryzen 3 3300X vs Intel Core i5-8259U Comparison

Head-to-Head Benchmarks

The data is unambiguous: the AMD Ryzen 3 3300X dominates the Intel Core i5-8259U across every recorded benchmark. In Cinebench R15 multicore, the Ryzen scores 1071 against Intel's 667, a 60.6% advantage. The single-core gap is even more pronounced, with the Ryzen posting 195 versus 94, a 107.4% delta. That is more than double the performance in a single-threaded workload.

Geekbench results follow the same pattern, though with a narrower margin. The Ryzen 3 3300X scores 5772 in multicore, while the Core i5-8259U manages 4168, a 38.5% lead. In single-core Geekbench, the AMD part reaches 1555, and the Intel chip scores 1207, a 28.8% difference. Across all four head-to-head tests, the Ryzen wins outright with a clean sweep of 4 wins to 0.

The average benchmark score places the Ryzen 3 3300X at 2148, slightly above the i5-8259U's 2108. This puts the AMD chip in the 47th percentile of all CPUs, while the Intel part sits at the 46th percentile. The Ryzen's nearest rivals include the Intel Core i5-10200H (2154, -0.3%) and the Intel Core i7-5950HQ (2158, -0.4%), showing the AMD part is essentially level with those options. The Intel i5-8259U's nearest rivals include the Intel Core i5-8500T (2110, -0.1%) and the AMD Ryzen 5 PRO 2400G (2101, 0.3%), indicating a similar standing in the broader database.

Where Each One Wins

The Ryzen 3 3300X wins every single benchmark category recorded. For users prioritizing raw compute throughput, the Cinebench R15 multicore result of 1071 versus 667 demonstrates a massive advantage in rendering and heavily threaded tasks. The Geekbench multicore score of 5772 versus 4168 reinforces this, suggesting strong performance in modern multi-threaded applications.

In single-threaded workloads, the Ryzen's advantage is even more striking. The Cinebench R15 single-core score of 195 versus 94 shows the Zen 2 architecture delivers far superior per-core performance. This translates to snappier response in lightly threaded software, from older games to productivity tools that rely on a single primary thread.

The Intel Core i5-8259U has no benchmark victories in the recorded data. However, it does hold a different market position entirely. As a mobile part with a 28 W TDP and integrated Iris Pro Plus 655 graphics, it targets thin-and-light laptops where the Ryzen 3 3300X, with its 65 W TDP and no integrated GPU, cannot physically fit. The Intel chip's end-of-life production status and 2018 release date indicate it is a legacy offering.

Architecture Differences

The two processors come from fundamentally different design philosophies. The AMD Ryzen 3 3300X uses the Zen 2 architecture, codenamed Matisse, built on TSMC's 7 nm process. It packs 3,800 million transistors into a 74 mm² die, a remarkably dense design. The Intel Core i5-8259U uses the older Coffee Lake architecture, codenamed Coffee Lake-U, on Intel's 14 nm process, with a significantly larger 126 mm² die.

Cache configurations differ substantially. The Ryzen 3 3300X has 64 KB of L1 cache per core and 512 KB of L2 per core, with a large 16 MB shared L3 cache. The Intel i5-8259U matches the L1 at 64 KB per core but drops to 256 KB of L2 per core and only 6 MB of shared L3. The Ryzen's larger L3 cache likely contributes to its benchmark dominance, particularly in single-threaded tests where cache latency matters.

Memory bandwidth also favors the AMD part. The Ryzen 3 3300X supports dual-channel DDR4 with a theoretical bandwidth of 51.2 GB/s, while the Intel i5-8259U offers dual-channel DDR4 at 38.4 GB/s. This 33% bandwidth advantage helps in memory-intensive workloads, possibly explaining part of the multicore performance gap.

PCIe connectivity differs as well. The Ryzen 3 3300X provides PCIe Gen 4 with 16 lanes from the CPU, while the Intel i5-8259U offers PCIe Gen 3 with 16 lanes. The newer Gen 4 standard doubles the available bandwidth per lane, which matters for high-speed NVMe storage and future GPU connectivity.

Specification Differences

The most obvious specification gap is the clock speed. The AMD Ryzen 3 3300X runs at a 3.80 GHz base clock and boosts to 4.30 GHz, while the Intel Core i5-8259U has a 2.30 GHz base and 3.80 GHz boost. The Ryzen's higher clocks across the board, combined with its architectural advantages, explain its performance lead.

Thermal design power tells the efficiency story. The Ryzen 3 3300X is rated at 65 W TDP, typical for a desktop part. The Intel i5-8259U is rated at 28 W TDP, reflecting its mobile design. This makes the Intel chip far more power-efficient on paper, but at the cost of sustained performance.

The socket and platform differ completely. The AMD part uses Socket AM4, a widely supported desktop platform with an unlocked multiplier, allowing overclocking. The Intel chip uses BGA 1526, a soldered mobile socket with no overclocking support. This fundamental difference means the two chips are not interchangeable in any system.

Integrated graphics separate them further. The Ryzen 3 3300X has no integrated GPU, requiring a discrete graphics card. The Intel i5-8259U includes Iris Pro Plus 655, making it a complete package for laptops without dedicated graphics. The Intel part also has a later release date in the database context, though the Ryzen launched later in real-world terms.

Other differences include the process node (7 nm versus 14 nm), foundry (TSMC versus Intel), and memory support details. Both support DDR4 dual-channel, but the Ryzen's higher bandwidth ceiling gives it an edge. Neither supports ECC memory. The Ryzen 3 3300X carries a launch MSRP of $120, while the Intel i5-8259U carries a launch MSRP of $320.

FAQ

Q: Which processor has better single-threaded performance?

A: The AMD Ryzen 3 3300X wins decisively. In Cinebench R15 single-core, it scores 195 versus Intel's 94, a 107.4% advantage. Geekbench single-core shows 1555 versus 1207, a 28.8% lead.

Q: Are both processors quad-core with eight threads?

A: Yes, both the AMD Ryzen 3 3300X and the Intel Core i5-8259U have 4 cores and 8 threads. This makes the performance gap purely a matter of architecture, clocks, and cache, not core count.

Q: Does the Intel Core i5-8259U have integrated graphics?

A: Yes, it includes Iris Pro Plus 655. The AMD Ryzen 3 3300X has no integrated graphics, requiring a separate GPU for display output.

Q: What is the memory bandwidth difference?

A: The AMD Ryzen 3 3300X supports 51.2 GB/s of dual-channel DDR4 bandwidth, while the Intel Core i5-8259U supports 38.4 GB/s. This is a 33% advantage for the AMD part.

Q: Can the Intel Core i5-8259U be overclocked?

A: No, it has a locked multiplier and uses the BGA 1526 socket, which is soldered. The AMD Ryzen 3 3300X has an unlocked multiplier on Socket AM4, allowing overclocking.

Q: Which processor has a higher average benchmark score?

A: The AMD Ryzen 3 3300X averages 2148, while the Intel Core i5-8259U averages 2108. The Ryzen sits at the 47th percentile of all CPUs, and the Intel chip at the 46th percentile.

The Verdict

The AMD Ryzen 3 3300X is the clear performance winner based on every recorded benchmark. It leads by 60.6% in Cinebench R15 multicore, 107.4% in single-core, 38.5% in Geekbench multicore, and 28.8% in Geekbench single-core. For any user building a desktop system where raw CPU performance is the priority, the data points squarely to the Ryzen.

The Intel Core i5-8259U is not without purpose, but its role is entirely different. As a 28 W mobile processor with integrated Iris Pro Plus 655 graphics, it serves thin-and-light laptops where power draw and space constraints rule out a desktop chip. Its end-of-life status and 2018 release date mean it is a legacy product, while the Ryzen remains active in production.

For desktop users, the Ryzen 3 3300X offers superior performance across the board, a more modern 7 nm process, larger cache, higher memory bandwidth, and PCIe Gen 4 support. Its 65 W TDP is higher, but that is irrelevant for a desktop platform designed to handle it. The unlocked multiplier adds flexibility for enthusiasts.

For mobile users, the Intel i5-8259U is the only viable option of the two, simply because the Ryzen 3 3300X does not exist in a mobile form factor. The Intel chip's lower TDP and integrated graphics make it suitable for laptops, while the Ryzen requires a discrete GPU and a desktop motherboard.

The benchmark data leaves no ambiguity: the Ryzen 3 3300X wins 4 out of 4 head-to-head tests. The Intel i5-8259U wins no tests. However, the mobile-versus-desktop split means these chips rarely compete in the same system. The verdict is straightforward: choose the Ryzen for desktop performance, and accept the Intel only if the mobile form factor is mandatory.