Upgrading the Lenovo Legion 5 15ARH05: RAM, storage and CPU
Updated Oct. 19, 2026 · Written from this device's verified specifications
The Legion 5 15ARH05 is the 2020 15-inch AMD model (machine types 82B1 and 82B5, Ryzen 5 4600H or Ryzen 7 4800H). Memory and SSD upgrades are straightforward; the processor is not upgradeable at all. Before you buy anything, one warning. A lot of the Legion 5 15-inch information online describes the 2021 sibling, the 15ACH6H (Type 82JU), which looks similar but has a different processor, graphics chip and in places a different storage layout. The memory and M.2 parts are the same kind in both machines, but the exact drive-bay arrangement of the 15ARH05 is not fully documented in the material we could check. Confirm your machine type on the sticker on the bottom of the laptop and look it up in Lenovo PSREF and the Hardware Maintenance Manual for the 15ARH05 before ordering.
At a glance
- RAM: 2x DDR4-3200 SO-DIMM slots, nothing soldered. Lenovo certifies 32 GB; 64 GB generally works.
- Storage: 2x M.2 2280 PCIe 3.0 x4 NVMe. A 2.5-inch SATA bay exists on some SKUs only.
- CPU: soldered in place — no upgrade path.
- The bottom panel is very stiff; use a plastic pry tool and take your time.
| 2x DDR4-3200 SO-DIMM slots (none soldered) | 2 × DDR4 SO-DIMM · up to 64 GB total · 3200 MT/s |
|---|---|
| 2x M.2 2280 NVMe + 2.5" SATA bay (SKU-dep.) | 3 × SSD / HDD M.2 2280 / 2.5" (NVMe / SATA) · max 7 mm thick |
Lifecycle and support
A current model: sold new and supported.
| Milestone | Date |
|---|---|
| Release First available to buy. |
August 2020
Estimate
North American on-sale month per contemporaneous third-party reporting; no manufacturer page gives an actual first-sale date. Lenovo's press release only gave an expected 'May 2020' window (https://news.lenovo.com/pressroom/press-releases/lenovo-legion-launches-gaming-pcs-to-new-levels-with-innovati Source ↗ |
Dates not listed haven't been published by the manufacturer or a reliable third party.
RAM (memory)
There are two DDR4 SO-DIMM slots and nothing is soldered to the board, so both sticks are replaceable and the slots sit under a small cover inside the case.
What fits: unbuffered, non-ECC DDR4-3200 SO-DIMMs (PC4-25600, 262-pin). Server memory, ECC or registered modules are not supported, and the machine takes standard laptop modules only — not desktop DIMMs.
The limit depends on who you ask. Lenovo certifies 16 GB per slot, 32 GB total, and that is the figure you will find in the official datasheets. In practice, a pair of 32 GB modules (64 GB total) generally works in this family, but that configuration is not certified and sources disagree on the maximum. If you want to stay on safe ground, stop at 32 GB; if you need 64 GB, buy from a seller with good returns in case your specific board objects.
Whatever capacity you choose, buy a matched pair (two identical modules) so the machine runs in dual channel, which makes a real difference to gaming and everyday speed on AMD integrated graphics and memory-sensitive workloads. Faster-than-3200 memory adds nothing here; the platform runs at 3200 MT/s.
Buying tips: DDR4-3200 SO-DIMM, 1.2 V, non-ECC, bought as a 2x kit. 2x8 GB or 2x16 GB are the sweet spots; only go to 2x32 GB if you know you need it.
Buying tips
- Matched 2x kit of DDR4-3200 SO-DIMMs (PC4-25600), non-ECC, unbuffered.
- 2x8 GB or 2x16 GB is enough for most owners; 2x32 GB works in practice but is not certified.
- Don't pay extra for 3600+ MT/s modules — this platform runs them at 3200.
Storage (SSD and hard drive)
The Legion 5 15ARH05 has two M.2 2280 slots (M-key) for PCIe NVMe solid-state drives. Both are PCIe 3.0 x4, so any modern NVMe SSD will work. A couple of traps to know about:
SATA-protocol M.2 drives are not supported in these slots. If the listing says 'M.2 SATA', it will not work here — look for 'M.2 NVMe' or 'PCIe'.
PCIe 4.0 NVMe drives do work, but they run at PCIe 3.0 speed, so there is no point paying a premium for a Gen4 drive in this laptop. A good Gen3 drive is the sensible buy.
Capacity: there is no documented cap for the 15ARH05, and 2 TB and 4 TB M.2 drives fit. Lenovo's published figures for the closely related models top out at 2 TB, but that is a sales ceiling rather than a hardware limit. If you want a very large drive, check reports for the exact model of SSD you are considering.
The 2.5-inch bay is where it gets messy. According to Lenovo's Hardware Maintenance Manual for this family, some 15ARH05 configurations have a 2.5-inch SATA 6 Gb/s bay that takes drives up to 7 mm thick — but other configurations leave it out entirely, and most laptops shipped without the hard-drive cable and caddy you would need. To find out what your machine has, take the bottom panel off and look, or check your serial number in Lenovo Parts Lookup. Do not order a 2.5-inch SSD or HDD until you have confirmed your unit has the bay and you have sourced the cable.
ARH05-specific storage details are not well covered in published documentation — most of the detailed material covers the 2021 15ACH6H, which has a different internal layout. Confirm the details for your exact machine type (82B1/82B5) before buying.
Buying tips: M.2 2280 NVMe, PCIe Gen3, from a mainstream brand. For the 2.5-inch bay, a 7 mm SATA SSD is the easy upgrade — but only after you have checked the bay exists on your unit.
Buying tips
- M.2 2280 NVMe PCIe SSD — not M.2 SATA. Gen3 drives are the right value here.
- 1 TB or 2 TB covers most people; larger drives fit but are less widely tested.
- For a 2.5-inch drive: verify your unit has the bay first, and remember the cable and caddy are often not included.
- The Wi-Fi module is also replaceable if yours is the weak point.
How to upgrade
Before you start
- Check your exact machine type (82B1/82B5) and look it up in Lenovo PSREF and the Hardware Maintenance Manual for the 15ARH05, so you know which storage layout your unit has.
- Match the part to what we have listed above before ordering — RAM that is not DDR4 SO-DIMM, or an M.2 SATA drive, will not fit.
Steps
- General installation outline
1. Back up anything you care about. Firmware and BIOS updates should also be done before a big hardware change if one is available for your machine type. 2. Shut the laptop down fully and unplug the power adapter. Remove any external devices. 3. Ground yourself — touch a metal object or use an anti-static strap — so you do not damage the new part or the board. 4. Open the case. On this model the bottom panel is extremely stiff even after all the screws are out: use a plastic pry tool and work slowly around the edge rather than pulling. The RAM and M.2 slots sit under additional small covers. For exact screw locations and disassembly order, follow the owner's manual or the Hardware Maintenance Manual for the 15ARH05. 5. Install the part. For RAM, line up the notch on the module with the slot and press it in at a slight angle until the side clips click. For an M.2 SSD, slide the drive into the slot and secure it with the retaining screw — do not force it, and do not use a SATA M.2 drive. 6. Close the case, making sure no cables are trapped and the panel clips are all seated. 7. Power on and check that the BIOS/UEFI and the operating system see the new part. If a drive does not appear, reseat it and check the BIOS storage settings.
Good to know
- RAM maximum: Lenovo says 32 GB; independent testing of the closely related model supports 64 GB. We cannot confirm 64 GB specifically on the 15ARH05.
- Storage limits: no capacity cap is documented for the 15ARH05; 2 TB and 4 TB M.2 drives fit in practice. Lenovo's published 'up to 2 TB' figure comes from the 2021 datasheets.
- The 2.5-inch bay is SKU-dependent and the cable is often not included — verify on your unit before ordering.
- Published documents for the 2021 15ACH6H describe a different processor and a somewhat different internal layout. Always confirm against PSREF and the Hardware Maintenance Manual for your exact machine type.
Frequently asked questions
How much RAM can the Lenovo Legion 5 15ARH05 take?
Lenovo certifies 16 GB per slot, 32 GB total, across its two SO-DIMM slots. In practice a pair of 32 GB modules (64 GB total) generally works in this family, but that is not certified and sources disagree on the maximum. Staying at 32 GB is the safe choice; 64 GB is a reasonable experiment if you buy from somewhere with good returns.
What type of RAM does the Legion 5 15ARH05 use?
DDR4-3200 SO-DIMMs (PC4-25600), unbuffered and non-ECC. Nothing is soldered, so both modules are replaceable. Buy a matched pair for dual channel — it makes a noticeable difference to performance.
How many SSDs can I install?
Two M.2 2280 NVMe drives fit in the dedicated slots, both PCIe 3.0 x4. Some configurations also have a 2.5-inch SATA bay for a third drive, but that bay is not present on every 15ARH05 SKU and the hard-drive cable is often missing from the box — check your unit before buying a 2.5-inch drive.
Does the Legion 5 15ARH05 support SATA M.2 drives?
No. The M.2 slots accept NVMe (PCIe) drives only. An M.2 SATA SSD will not work in them. PCIe 4.0 NVMe drives do work, but only at PCIe 3.0 speed.
Can I upgrade the CPU in my Legion 5 15ARH05?
No. The Ryzen 5 4600H or Ryzen 7 4800H is soldered to the motherboard, so there is no socket and no upgrade path. Chips from newer models cannot be fitted either. Keeping the cooling system clean is the best you can do for CPU performance.
Do all Legion 5 15ARH05 laptops have a 2.5-inch hard drive bay?
No. Lenovo's maintenance documentation shows a 2.5-inch SATA 6 Gb/s bay (up to 7 mm thick) on some configurations, while others leave it out, and many units ship without the required cable and caddy. Confirm by opening the case or checking your serial number in Lenovo's parts lookup before ordering a 2.5-inch drive.
Official documents and references
- PDF Lenovo PSREF datasheet, Legion 5 15ACH6H (official Lenovo specification sheet)
Official Lenovo spec sheet, but for the 2021 15ACH6H sibling. The memory and M.2 parts it describes are the same kind as in the 15ARH05; the CPU, GPU and storage layout are not identical. - PDF Lenovo Legion 5 AMD 15-inch datasheet (official Lenovo PDF)
Also official, also covering the 2021 generation — useful for memory and M.2 specifications, not for ARH05-specific bay details. - Notebookcheck: Lenovo Legion 5 15 series overview (includes the 2020 15ARH05H)
Series page that lists the 2020 15ARH05H configuration (Ryzen 7 4800H, GTX 1660 Ti), useful for confirming which generation you own. - Notebookcheck review: Legion 5 15 G6 AMD (2021 sibling)
Detailed hands-on with the 2021 15ACH6H, including memory slots, M.2 slots and the stiff bottom panel. Read it as a close relative of the 15ARH05, not as documentation for it.