AMD Ryzen 9 9955HX vs AMD Ryzen AI Max+ 388 Comparison

Where Each One Wins

The benchmark record for this comparison is unusually one-sided. The AMD Ryzen 9 9955HX wins all 15 recorded head-to-head tests, with zero wins for the AMD Ryzen AI Max+ 388. The closest margin appears in single-threaded workloads, while the largest gaps emerge in heavily parallel tasks. This is not a balanced contest; it is a clear tier separation driven by core count, memory architecture, and the specific workloads each chip is designed to accelerate.

The Ryzen 9 9955HX dominates in multi-core compute. Its Cinebench R23 multi-core score of 37159 versus 18759 for the AI Max+ 388 represents a 98.1% advantage, meaning the 9955HX delivers nearly double the rendering throughput. Similarly, Cinebench R15 multi-core shows a 105.6% lead (5905 versus 2872). For workloads that scale across threads, such as video encoding, 3D rendering, batch photo processing, or scientific simulation, the 9955HX is the clear choice. The 16-core, 32-thread configuration simply overwhelms the 8-core, 16-thread part.

Where the AI Max+ 388 might have been expected to shine is in memory bandwidth-sensitive tasks. The database shows it supports quad-channel LPDDR5X with 256.0 GB/s of bandwidth, versus dual-channel DDR5 at 89.6 GB/s for the 9955HX. That is a 2.86x raw bandwidth advantage. Still, the recorded PassMark results do not reflect any win for the AI Max+ 388. In data compression, the 9955HX scores 731998 versus 400887, an 82.6% lead. In integer math, the lead is 94% (212598 versus 109588). The bandwidth advantage does not translate into benchmark wins, likely because the 9955HX's extra cores and higher boost clock compensate in these specific tests.

Single-thread performance is closer but still favors the 9955HX. The PassMark single-thread score is 4393 versus 4185, a 5% margin. Cinebench R23 single-core shows a 10.9% lead (2174 versus 1960), and Cinebench R15 single-core shows 12.8% (336 versus 298). For everyday responsiveness, light productivity, or lightly threaded applications, both chips are competitive, but the 9955HX holds a measurable edge.

The AI Max+ 388 is not without purpose. Its integrated graphics, the Radeon 8060S, is far more capable on paper than the Radeon 610M found in the 9955HX. The database does not include graphics benchmarks, so this cannot be quantified here. But the memory system, quad-channel LPDDR5X at 256.0 GB/s, is clearly built to feed a large integrated GPU. The 9955HX, with 28 PCIe Gen 5 lanes, is designed for a discrete GPU. The use-case split is straightforward: the 9955HX for CPU-bound multi-threaded work, the AI Max+ 388 for compact systems that need strong integrated graphics and high memory bandwidth without a discrete card.

Architecture Differences

Both processors are built on TSMC's 4 nm process node and both use the Zen 5 architecture. The die size is identical at 2x 70.6 mm². The transistor count for the 9955HX is recorded as 16,630 million, while the AI Max+ 388 does not have a listed transistor count in the database. The core counts differ significantly: the 9955HX has 16 cores and 32 threads, while the AI Max+ 388 has 8 cores and 16 threads. Both share the same per-core cache configuration, with 80 KB of L1 and 1 MB of L2 per core. The L3 cache is the major difference: the 9955HX has 64 MB shared, while the AI Max+ 388 has 32 MB shared.

Clock speeds favor the 9955HX in boost but the AI Max+ 388 in base clock. The 9955HX runs at a 2.50 GHz base and 5.40 GHz boost, while the AI Max+ 388 runs at 3.60 GHz base and 5.00 GHz boost. The higher base clock on the AI Max+ 388 suggests it maintains higher sustained frequencies at low thread counts, but the 9955HX's higher boost clock gives it the edge in peak single-thread performance.

Memory support is a fundamental split. The 9955HX uses DDR5 over a dual-channel bus, yielding 89.6 GB/s. The AI Max+ 388 uses LPDDR5X over a quad-channel bus, yielding 256.0 GB/s. Both support ECC memory. The AI Max+ 388's bandwidth is nearly triple, which is a deliberate design choice for feeding its integrated Radeon 8060S graphics. The 9955HX, by contrast, relies on a discrete GPU and thus has a narrower memory bus.

PCIe connectivity also differs. The 9955HX offers Gen 5 with 28 lanes (CPU only), while the AI Max+ 388 offers Gen 4 with 16 lanes (CPU only). The 9955HX is the more expandable platform for high-speed storage and external GPUs. The AI Max+ 388 is more limited in expansion but does not need the extra lanes for its integrated graphics approach.

The sockets are different: AMD Socket FL1 for the 9955HX, AMD Socket FP11 for the AI Max+ 388. The multiplier is unlocked on the 9955HX, while the AI Max+ 388 has a locked multiplier. The 9955HX is part of the 9000 series with the codename Fire Range, while the AI Max+ 388 is from the Ryzen AI Max series with the codename Strix Halo. The 9955HX was released on 2025-01-05, and the AI Max+ 388 on 2026-01-05. Both are listed as Active in production.

Head-to-Head Benchmarks

The most decisive win for the 9955HX is in Cinebench R15 multi-core, where it scores 5905 against 2872, a 105.6% advantage. This is the only test in the entire suite where the margin exceeds 100%. The second-largest is Cinebench R23 multi-core at 98.1% (37159 versus 18759). These two tests establish the 9955HX as a dominant multi-threaded performer.

PassMark integer math shows a 94% lead (212598 versus 109588), and floating-point math shows an 88% lead (136682 versus 72722). Find prime numbers, a classic CPU stress test, shows a 97.9% gap (287 versus 145). Data encryption shows 85.8% (37330 versus 20092), and data compression shows 82.6% (731998 versus 400887). Random string sorting shows 80.3% (77890 versus 43196), and extended instructions show 77.1% (57946 versus 32719).

The PassMark multi-thread score is 56171 versus 33486, a 67.7% lead. PassMark physics shows 2720 versus 1843, a 47.6% lead. These are still substantial margins, but they are smaller than the Cinebench results, suggesting that the AI Max+ 388 handles some parallel workloads relatively better than others.

The single-thread tests are the closest. PassMark single-thread shows 4393 versus 4185, a 5% lead. Cinebench R23 single-core shows 2174 versus 1960, a 10.9% lead. Cinebench R15 single-core shows 336 versus 298, a 12.8% lead. The 9955HX wins all of these, but the margins are modest. For a user whose primary workload is lightly threaded, the difference between the two chips would be noticeable but not transformative.

The overall average benchmark score tells the same story. The 9955HX averages 91199 across all recorded tests, placing it in the 96th percentile of all CPUs. The AI Max+ 388 averages 49796, placing it in the 90th percentile. The nearest rival to the 9955HX is the Intel Xeon 654 with an average score of 90717 and a delta of 0.5%, meaning the 9955HX is essentially tied with that server part. The nearest rival to the AI Max+ 388 is the Intel Core 9 273PE with an average score of 49845 and a delta of -0.1%, a negligible difference. The AI Max+ 388 also sits close to the AMD Ryzen 9 7900 (49228, delta 1.2%) and the Intel Core i5-14600KF (49394, delta 0.8%). These rival comparisons contextualize the gap: the 9955HX competes with high-end server and desktop parts, while the AI Max+ 388 competes with mid-range desktop CPUs.

FAQ

Q: Which CPU has more cores and threads?

A: The AMD Ryzen 9 9955HX has 16 cores and 32 threads. The AMD Ryzen AI Max+ 388 has 8 cores and 16 threads.

Q: Which CPU has higher memory bandwidth?

A: The AMD Ryzen AI Max+ 388 has higher memory bandwidth at 256.0 GB/s via quad-channel LPDDR5X. The AMD Ryzen 9 9955HX has 89.6 GB/s via dual-channel DDR5.

Q: Which CPU wins in single-threaded performance?

A: The AMD Ryzen 9 9955HX wins all recorded single-thread tests. PassMark single-thread shows a 5% lead (4393 versus 4185), and Cinebench R23 single-core shows a 10.9% lead (2174 versus 1960).

Q: Which CPU has a higher boost clock?

A: The AMD Ryzen 9 9955HX has a boost clock of 5.40 GHz. The AMD Ryzen AI Max+ 388 has a boost clock of 5.00 GHz.

Q: Which CPU supports PCIe Gen 5?

A: The AMD Ryzen 9 9955HX supports PCIe Gen 5 with 28 lanes. The AMD Ryzen AI Max+ 388 supports PCIe Gen 4 with 16 lanes.

Q: What is the average benchmark score for each CPU?

A: The AMD Ryzen 9 9955HX has an average benchmark score of 91199, which places it in the 96th percentile of all CPUs. The AMD Ryzen AI Max+ 388 has an average score of 49796, placing it in the 90th percentile.

The Verdict

The data is unambiguous. The AMD Ryzen 9 9955HX is the superior CPU in every recorded benchmark, with 15 wins out of 15 head-to-head tests. Its multi-core advantage is massive, ranging from 47.6% in PassMark physics to 105.6% in Cinebench R15 multi-core. For any workload that scales across cores, the 9955HX delivers roughly double the performance of the AI Max+ 388 in the most demanding tests.

The AI Max+ 388 is not a weak processor. Its average benchmark score of 49796 places it in the 90th percentile of all CPUs, and it sits within 1.2% of desktop parts like the AMD Ryzen 9 7900 and the Intel Core i5-14600KF. But its 8-core configuration and 32 MB of L3 cache limit it in multi-threaded work. The 9955HX, with 16 cores, 64 MB of L3, and a 5.40 GHz boost clock, is in a different performance class, as evidenced by its 96th percentile ranking and its proximity to the Intel Xeon 654.

The choice between these two comes down to the platform, not raw CPU performance. The AI Max+ 388 uses the Radeon 8060S integrated graphics and quad-channel LPDDR5X memory with 256.0 GB/s of bandwidth, which is a configuration built for compact systems that avoid discrete GPUs. The 9955HX uses the Radeon 610M integrated graphics, dual-channel DDR5, and 28 PCIe Gen 5 lanes, which is a configuration designed to pair with a high-end discrete graphics card. The 9955HX also has an unlocked multiplier, making it the choice for overclocking, while the AI Max+ 388 does not.

For a buyer who needs maximum CPU throughput, especially in multi-threaded rendering, encoding, or simulation, the 9955HX is the only choice. For a buyer who needs a powerful integrated GPU and high memory bandwidth in a single package, the AI Max+ 388 is the relevant option, though its CPU performance will trail the 9955HX by substantial margins in every recorded test. The database does not contain graphics benchmarks, so the AI Max+ 388's integrated GPU advantage cannot be quantified, but the memory system and Radeon 8060S designation indicate its intended role. The verdict is clear: the 9955HX wins on CPU performance, and the AI Max+ 388 wins on integrated graphics capability, which is not measured in this comparison.