AMD Ryzen 7 7800X3D vs AMD Ryzen 7 8840HS Comparison

The AMD Ryzen 7 8840HS and the AMD Ryzen 7 7800X3D share the same core count and Zen 4 architecture, but they are engineered for entirely different environments. The recorded data shows a decisive overall victory for the desktop part, with the 7800X3D winning 16 of 17 head-to-head benchmarks. However, the single benchmark win for the 8840HS, along with its dramatically lower power envelope, reveals a clear split in intended use cases. The 8840HS is a mobile processor designed for efficiency and integrated graphics, while the 7800X3D is a desktop processor built for maximum throughput and gaming performance.

Where Each One Wins

The AMD Ryzen 7 7800X3D wins in virtually every compute-heavy category. The data shows it leads in multi-threaded workloads, single-threaded performance, and specialized instruction tests. Its largest margins come in tasks that stress raw processing power or cache sensitivity. The 8840HS, conversely, only wins in one specific scenario: Cinebench R23 single-core, where it edges ahead by 1.4%. This suggests that for lightly threaded, short-duration tasks, the mobile chip's higher boost clock can compensate for its lower base power.

The use-case split is stark. The 7800X3D is the choice for desktop workloads where sustained performance matters: rendering, data compression, encryption, physics calculations, and integer math. The 8840HS, with its 28 W TDP and integrated Radeon 780M graphics, is positioned for thin-and-light laptops where power draw and heat generation are critical constraints. Its win in Cinebench R23 single-core indicates it can handle bursty, single-threaded productivity tasks without sacrificing efficiency. The 7800X3D, with a 120 W TDP, is not suited for battery-powered devices, but it dominates in any scenario where wall power is available.

Architecture Differences

Both processors are built on TSMC manufacturing, but they use different process nodes. The 8840HS uses a 4 nm node and packs 25,000 million transistors on a 178 mm² die. The 7800X3D uses a 5 nm node with 11,270 million transistors on a 71 mm² die. This difference is significant: the mobile chip integrates more transistors on a larger die, likely due to its integrated Radeon 780M graphics and other mobile-specific components. The desktop chip, despite its smaller transistor count, compensates with a massive cache advantage.

The 7800X3D features 96 MB of shared L3 cache, compared to 16 MB on the 8840HS. This 80 MB difference is the defining architectural feature of the 7800X3D. The codename for the desktop part is Raphael, while the mobile part is Hawk Point. Both use the Zen 4 architecture, but the desktop part is built for desktop sockets (AM5) while the mobile part uses Socket FP8. The 7800X3D supports ECC memory, while the 8840HS does not. The desktop chip also offers PCIe Gen 5 with 24 lanes, whereas the mobile chip is limited to PCIe Gen 4 with 20 lanes. The memory bandwidth figures differ as well: the 8840HS records 89.6 GB/s versus 83.2 GB/s for the 7800X3D, despite the desktop chip's faster base clock.

Head-to-Head Benchmarks

The benchmark data shows a sweeping victory for the 7800X3D across most tests. In Cinebench R23 multi-core, the desktop part scores 16817 against 13082, a 22.2% advantage. The gap widens in Geekbench multi-core, where the 7800X3D scores 15610 versus 10104, a 35.3% lead. In PassMark multi-thread, the 7800X3D scores 34293 against 24990, a 27.1% difference. These results confirm that the desktop chip's higher base clock (4.20 GHz vs 3.30 GHz) and larger cache translate directly into sustained multi-core performance.

The most extreme deltas appear in specialized tests. In PassMark find prime numbers, the 7800X3D scores 324 against 79, a massive 75.6% advantage. PassMark physics shows a 67.4% lead (3522 vs 1149). These tests are likely sensitive to cache size and memory latency, where the 96 MB L3 cache on the 7800X3D provides a decisive edge. Even in floating-point math, where the gap is smaller, the 7800X3D still leads by 14.1% (61187 vs 52582). Integer math shows a 12.8% advantage (103639 vs 90382).

Single-threaded results are closer but still favor the desktop part. In Geekbench single-core, the 7800X3D scores 2426 against 1899, a 21.7% lead. PassMark single-thread shows a 3.5% edge (3759 vs 3626). Cinebench R15 single-core shows a 4.1% lead for the 7800X3D (281.5 vs 270). However, Cinebench R23 single-core is where the 8840HS wins: it scores 1737 against 1713, a 1.4% advantage. This narrow win indicates that the mobile chip's 5.10 GHz boost clock can outperform the desktop chip's 5.00 GHz boost in specific short workloads.

Specification Differences

The two processors differ in several key specifications. The 8840HS has a base clock of 3.30 GHz and a boost clock of 5.10 GHz, while the 7800X3D has a base clock of 4.20 GHz and a boost clock of 5.00 GHz. The desktop chip has a higher TDP of 120 W, compared to the mobile chip's 28 W. The socket types differ: FP8 for the mobile part, AM5 for the desktop part.

The cache hierarchy differs significantly. Both have 64 KB L1 and 1 MB L2 per core, but the L3 cache is 16 MB shared on the 8840HS versus 96 MB shared on the 7800X3D. Memory bandwidth is higher on the mobile chip (89.6 GB/s vs 83.2 GB/s), but the desktop chip supports ECC memory while the mobile chip does not. PCIe capabilities differ: Gen 4 with 20 lanes for the mobile chip, Gen 5 with 24 lanes for the desktop chip. The integrated graphics differ: Radeon 780M on the 8840HS versus Radeon Graphics on the 7800X3D. The release dates differ: the 8840HS launched in December 2023, while the 7800X3D launched in January 2023. The 8840HS has a launch MSRP of none recorded, while the 7800X3D has a launch MSRP of $449. The 7800X3D is a desktop part with a 7000 series designation, while the 8840HS is an 8000 series mobile part. The part numbers differ as well, with the 8840HS having multiple FP7r2, FP7, and FP8 variants.

FAQ

Q: Which processor has the higher boost clock?

A: The AMD Ryzen 7 8840HS has a boost clock of 5.10 GHz, while the AMD Ryzen 7 7800X3D has a boost clock of 5.00 GHz.

Q: How much larger is the L3 cache on the 7800X3D?

A: The 7800X3D has 96 MB of shared L3 cache, which is 80 MB more than the 16 MB on the 8840HS.

Q: Which processor supports ECC memory?

A: The AMD Ryzen 7 7800X3D supports ECC memory, while the AMD Ryzen 7 8840HS does not.

Q: What is the TDP difference between the two?

A: The 7800X3D has a TDP of 120 W, while the 8840HS has a TDP of 28 W.

Q: In which benchmark does the 8840HS outperform the 7800X3D?

A: The 8840HS wins in Cinebench R23 single-core, scoring 1737 against 1713, a 1.4% advantage.

Q: What is the memory bandwidth for each processor?

A: The 8840HS has a memory bandwidth of 89.6 GB/s, while the 7800X3D has a memory bandwidth of 83.2 GB/s.

The Verdict

The data is unambiguous: the AMD Ryzen 7 7800X3D is the superior processor for almost all compute tasks. It wins 16 of 17 head-to-head benchmarks, with its most dominant margins in prime number calculations (75.6% ahead), physics (67.4% ahead), and Geekbench multi-core (35.3% ahead). The desktop chip's 96 MB L3 cache and higher base clock make it the clear choice for desktop users who need maximum performance in rendering, data processing, and cache-sensitive workloads. Its percentile rank of 83 versus the 8840HS's 84 is nearly identical, but the average benchmark score favors the 7800X3D at 33079 versus 33667 for the mobile chip, a negligible difference that hides the per-test deltas.

The AMD Ryzen 7 8840HS is not without merit. Its single win in Cinebench R23 single-core (1.4% ahead) shows that its 5.10 GHz boost clock can deliver competitive single-threaded performance in short bursts. More importantly, its 28 W TDP, integrated Radeon 780M graphics, and mobile socket make it the only viable option for laptops. The 8840HS also has a higher memory bandwidth (89.6 GB/s vs 83.2 GB/s) and a smaller process node (4 nm vs 5 nm), which contributes to its efficiency.

For a desktop builder, the 7800X3D is the obvious pick. It offers dramatically better multi-threaded performance, superior cache, and PCIe Gen 5 support. For a laptop buyer, the 8840HS is the only choice, and its single-core win indicates it can handle everyday tasks without issue. The 7800X3D's launch MSRP of $449 reflects its desktop positioning, but the price is secondary to the performance gap. The verdict is simple: buy the 7800X3D for a desktop, and the 8840HS for a mobile system. Neither is a bad processor, but they serve entirely different markets.