Intel Arrow Lake processors bottleneck PCIe 5.0 NVMe SSDs by 16%, limiting peak speeds to 12Gb/s instead of 14Gb/s
Thankfully, the issue does not impact PCIe M.2 add-in cards

Latency issues surrounding Intel's Core 200S series CPUs affect M.2 storage ports on LGA 1851 motherboards, leading to reduced performance. The SSD review reports that Arrow Lake CPUs have a bottleneck on the PCIe lanes dedicated to motherboard M.2 slots, causing a (roughly) 2GB/s bandwidth reduction compared to previous-gen motherboards when using the fastest and Best SSDs available.
The storage-focused review outlet initially discovered the flaw during testing when a 14GB/s-capable PCIe 5.0 SSD only achieved 12GB/s in an Arrow-Lake-based test rig. After reaching out to board makers and Intel, it was found that the issue is Arrow Lake-specific. The review outlet has been unable to confirm any Z890 motherboards operating PCIe 5.0 SSDs at speeds beyond 14GB/s, whereas previous-gen Z790 boards have no problem hitting the maximum speeds.
The review outlet demonstrated the aforementioned issues with a Samsung 9100 Pro and Micron 4600 SSD paired to two systems running a Z890 (Arrow Lake) and a Z790 (Raptor Lake) motherboard. With the Z890 motherboard, the Samsung and Micron SSDs peaked at 12.3GB/s in the board's primary and secondary M.2 slots.
Both SSDs reached speeds of up to 14.3GB/s on the Z790 motherboard. Furthermore, the review outlet tested both SSDs on an Asus Hyper M.2 add-in PCIe card and found both drives could achieve 14.3GB/s as well, confirming the issue only affects bandwidth on the physical M.2 slots on Z890 motherboards. Although sequential read/write performance improved, random performance remained behind the levels observed on older Z790 motherboards, indicating the latency issue persists even when bypassing the M.2 slot.
Further analysis confirmed that such performance limitations were not isolated to any specific motherboard maker. Asus and ASRock replicated the results independently and explained that the issue originates from the latency introduced by the I/O Extender component in Intel's new multi-chip processor layout.
This bizarre performance issue is allegedly a problem with Intel's interconnect on its latest Arrow Lake-based processors, resulting in unusual latency behavior among the chip's PCIe lanes. Intel's Core Ultra 200S-series processors for desktops feature 24 PCIe lanes: 16 PCIe 5.0 lanes for add-in graphics cards, four PCIe 5.0 lanes for SSD, and four PCIe 4.0 lanes for SSD. The first 16 PCIe lanes are controlled directly by the SoC tile of Intel's Arrow Lake-S CPUs. However, PCIe lanes 21 through 24 are routed through the I/O Extender tile, which adds latency and lowers peak bandwidth.
"Intel can confirm that the PCIe lanes 21 to 24 PCI Gen5 root port on Intel Core Ultra 200S series processors may exhibit increased latencies compared to the PCIe lanes 1 to 16 Gen5 root ports, owing to a longer die-to-die data path," a statement by Intel published by SSDReview reads. "However, any variations are contingent upon the specific workload and the capabilities of the PCIe endpoint device."
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This is now the second major performance-related issue affecting Arrow Lake processors. Intel's transition from a monolithic die design to a chiplet-style architecture with Arrow Lake has been widely known to affect gaming performance compared to previous generations of Intel processors. For instance, we've found that Intel's previous generation Core i9-13900K and i9-14900K flagships are significantly faster than the Core Ultra 9 285K gaming workload on average (based on our review of the Core Ultra 9 chip).
Intel has provided a firmware update(s) since our review to help alleviate gaming performance, but even with these updates, the chips still struggle to compete against previous-gen Raptor Lake predecessors in gaming scenarios.
Now that NVMe-based storage drives are having similar issues, it appears Intel's firmware development team has more work to do to rectify Arrow Lake's performance regressions, primarily caused by the architecture's switch to a chiplet-style design. It doesn't appear that Intel can fix these issues with firmware, so we'll likely have to wait for Intel's next-generation parts before these issues get fixed.
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Aaron Klotz is a contributing writer for Tom’s Hardware, covering news related to computer hardware such as CPUs, and graphics cards.
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endocine this performance gap may not be perceptible in everyday usage, but if you are paying a premium for the speed and cant get the full spec out of the component its yet another black eye for intel. At least its not burning out the CPU tho amiright?Reply -
bit_user I wonder if either QoS, or prioritizing CPU memory traffic above PCIe, play any role in this.Reply -
das_stig 200 series getting to be more and more an Intel Vista moment but the bad news for Intel, there are real alternatives from of companies, while the alternative for Vista was still a Microsoft product.Reply -
Amdlova Ssd transfers need to be reviewed on Linux. Micosoft don't push to the limit always have some interference of windows apps.Reply -
bit_user
Whether or not that's an issue, they're comparing performance between two different CPU + motherboard chipset combos under the same software configuration. So, unless it's a driver problem (which you'd expect Intel to have told them, if true), the OS isn't the issue here.Amdlova said:Ssd transfers need to be reviewed on Linux. Micosoft don't push to the limit always have some interference of windows apps. -
Pointingouttheobvious Stop with the lake codename nonsense. Its useless to the consumer. I get that you want to sound informed and technical but literally after 25+ freaking “lakes” i just want to see the “Ultra 100” or “Ultra 200” series or “14th gen” etc. something that actually translates to real world marketing materials. INTEL DOES NOT PUT “ARROW LAKE” ON A LAPTOP BOX. STOP IT.Reply -
bit_user
The first sentence of the article states that they're talking about the Core 200S series CPUs. They further reference specific motherboard chipset numbers, which are an official product designation. Fair enough that they don't mention the CPU family of the Z790 boards, other than by its code name.Pointingouttheobvious said:Stop with the lake codename nonsense.
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i just want to see the “Ultra 100” or “Ultra 200” series or “14th gen” etc.
FYI, I'd also just mention that they do include a link to the source article, in the second sentence, for those wishing to see more details. There's also a discussion of the CPU models concerned, in the 3rd paragraph from the bottom. -
watzupken I don't really think this is a big issue. There are not that many use cases that makes use of the full transfer rate of a PCI-E 5.0 SSD.Reply -
bit_user
Yeah, I'm not concerned about it, per se, but more intrigued by what it reveals about Arrow Lake's SoC.watzupken said:I don't really think this is a big issue. There are not that many use cases that makes use of the full transfer rate of a PCI-E 5.0 SSD.