TinySecrets

Tiny secrets

Here is my research with as many technical details about Lenovo’s, Dell’s, HP’s and Acer’s small PCs as I can find
There’s some interesting modding opportunities that haven’t been explored yet as far as I can tell, and I don’t have access to most of the hardware to try it myself

Below is an overview of the different system boards used inside each model, with the shipped vs theoretical maximum potential configuration

See the boardpics directory for high-resolution images of each model’s system board, taken from Lenovo’s parts webpage

See the riserpics directory for images of each type of PCIe riser I’m aware of

Table of contents:

• Lenovo

  • Mods

  • Risers

  • PCIe info

• Dell

• HP

• Acer

• Schematics

• Help out!

Lenovo Tiny Motherboard comparison table

lol this was a pain to format

BTB modules

todo

Random extra notes

• Starting with the Tiny5 generation, the riser slot contains 2 PCIe links, a x8 link from the CPU and a x4 link from the PCH. The PCH link supports hot-plug (don’t try it) and is for Thunderbolt support, the CPU link is for GPUs
• On the M90q gen 1 (NM-C901) schematic, the riser slot contains a bunch of extra IO for a supposed BMC card and riser with multiple slots (multiple refclks), possibly meant for unreleased server models?
• The M90q gen 1 schematic also has some extra IO on one of the M-key M.2 slots on the bottom, for some kind of dock-like device. Schematic mentions some special version for internal use at Amazon? Not sure if this is present on other models, no schematic available.
• M70q gen 1 and 2 boards are different from the M90q ones, but look nearly identical except for the CPU VRM config
• I’m not sure what the marketed difference between the M70q gen 3 and 4 and the M80q gen 3 and 4 is since they both support vPro
• Starting with the Tiny6 generation, most boards have unpopulated B-key M.2 WWAN and SIM card slots, might be meant for IoT/Edge/Server versions like the ThinkEdge SE50, but I can’t find any other model beyond that one.
• The M90q gen 2 and P350 have an unpopulated footprint for a 3rd M-key M.2 NVMe slot, would be cool to try soldering that on and seeing if it works.

Schematic observations / possible mods

Tiny5 2nd NVMe mod by badger707: https://github.com/badger707/m920q-dual-NVME
Tiny5 PCIe bifurcation mod by badger707: https://github.com/badger707/m920q-pcie-bifurcation

Board ID straps

Many of these boards have a set of resistor straps that are used to set the specific SKU of the system, they often share the same board and firmware. At its simplest there is of course the different tiers from the main series, but there’s also some interesting options:

• NEC variants are for the NEC rebranded versions of these systems, setting it reduces the amount of BIOS settings and changes the boot logo to the NEC logo
• Server and Amazon versions in the Tiny6 generation? Neither of these exist publicly as far as I know, I’d love to know more about them.
• Different versions of the M70q and M80q gen 1? (LI and LC)

ID straps from Tiny5 gen NM-B551

ID straps from Tiny6 gen NM-C901

Power rail capacity

Tiny5 NM-B551:

• 12V: 5.5A(66W), 10A(120W) OCP
• 5V: 16A(80W)
• 3.3V: 14A(46.2W)
• CPU Core max rating is 104A for 35W and 133A for 65W

12V rail OCP threshold can be increased by replacing PR1111 (12kΩ stock) with a larger size resistor (15kΩ-20kΩ) range, helps prevent shutdowns from GPU power spikes.

PR1111 (Rocset) location on board and in circuit diagram

Tiny6 NM-C901 & NM-C621:

• 12V: 10A(120W), 15A(180W) OCP (models with riser slot)
• 12V: 2A(24W), 5.1A(61.2W) OCP (models without riser slot)
• 5V: 16A(80W)
• 3.3V: 14A(46.2W)
• CPU Core max rating is 104A for 35W and 133A for 65W

12V is shared between PCIe slot and fans

PSU ID / Current limiting circuit

Tiny5 NM-B551:

System current limit is configured by ADP_ID signals (controlled by EC based on PSU detection) connecting different combinations of PR233, PR234 (30K for 65W, 14.3K for 35W) and PR235 to the current limiter setting pin. Exceeding the limit triggers prochot and throttles the CPU.

Full system current limit:

• 3.86A with 65W charger (35W models)
• 4.03A with 65W charger (65W models)
• 5.18A with 90W charger (35W models)
• 5.04A with 90W charger (65W models)
• 6.97A with 135W charger (35W & 65W models)

System doesnt detect higher powered supplies and current limit can’t be set to allow any additional power above it, may even default to 65W limit on larger supplies (needs more research)

Unpopulated / unused options

Tiny5 NM-B551 VRM:

M920X and P330 have an additional VRM phase (PU404) allowing for more current draw for 65W CPU (list of parts below).
There are also unpopulated capacitors PC458 and PC482 (in all versions) refitting which could smooth CPU power spikes.

Riser types

Official

3rd party

Links:
Tinyriser: https://github.com/a-little-wifi/Tinyriser
Tinyriser6: https://github.com/a-little-wifi/Tinyriser6
Tiny5 M.2 Riser: https://github.com/j4cbo/tiny5-m2-riser
PowerRiser: https://github.com/nandfarm/PowerRiser
M90-PowerRiser: https://github.com/nandfarm/M90-PowerRiser
Tiny6-X4+M2+M2+TF: https://github.com/qq8322302/Tiny6-P340-pcie-bifurcation-expansion-card
Tiny4/Tiny5 qq8322302: https://github.com/qq8322302/Lenovo-Tiny-Serial-PCIE-Expansion-Card

Pictures:
https://github.com/a-little-wifi/TinySecrets/tree/main/riserpics

Tiny8 x16 riser issues:

There seem to be problems with certain PCIe cards not working in the official Tiny8 x16 riser, mostly x4 and x1 width cards.
It does not seem to be an issue with the PRSNT pins on the PCIe slot, it’s been confirmed that there is continuity between the pins for x1, x4 and x8 to the one for x16.
I can’t really figure out why some cards wouldn’t be working in this riser, maybe something weird about the CPU lanes only supporting certain kinds of cards on this generation?
Any information about known working/not working cards would be helpful to see if there’s any pattern/consistency to it.

PCIe layout

todo

Tiny5:

M720q, M920q, M920x and P330 (NM-B551):

• DMI 3.0 x4 from CPU to PCH (B360 or Q370)
• Riser PCIe 3.0 x8 from CPU (lanes 0-7)
• Riser PCIe 3.0 x4 from PCH (lanes 9-12)
• SSD1 PCIe 3.0 x4 from PCH (lanes 21-24)
• SSD2 PCIe 3.0 x4 from PCH (lanes 17-20) (SATA support on lane 17) (PCIe not supported on B360/M720q, only SATA)
• 2.5" SATA 6Gb/s from PCH (lane 13)
• LAN PCIe 3.0 x1 from PCH (lane 5)
• Wifi PCIe 3.0 x1 from PCH (lane 6)
• BTB USB 3.0 from PCH (lane 1) (not supported on B360/M720q)

Tiny6:

M70q gen 1 and M80q gen 1 (NM-C621):

• DMI 3.0 x4 from CPU to PCH (H470 or Q470)
• ?

P340 and M90q gen 1 (NM-C901):

• DMI 3.0 x4 from CPU to PCH (Q470)
• Riser PCIe 3.0 x8 from CPU (lanes 8-15)
• Riser PCIe 3.0 x4 from PCH (lanes 9-12)
• SSD1 PCIe 3.0 x4 from PCH (lanes 21-24)
• SSD2 PCIe 3.0 x4 from PCH (lanes 17-20) (SATA support on lane 17)
• 2.5" SATA 6Gb/s from PCH (lane 13)
• LAN PCIe 3.0 x1 from PCH (lane 5)
• Wifi PCIe 3.0 x1 from PCH (lane 6)
• BTB USB 3.0 from PCH (lane 1)
• USB-C USB 3.0 from PCH (lane 2)
• WWAN PCIe 3.0 x1 from PCH (lane 15)

Tiny7:

P350 and M90q gen 2 (NM-D321):

• DMI 3.0 x8 from CPU to PCH (Q570)
• Riser PCIe 3.0 x8 from CPU (lanes 0-7)
• SSD1 PCIe 4.0 x4 from CPU (lanes ?-?)
• SSD2 PCIe 4.0 x4 from CPU (lanes ?-?)
• SSD3 PCIe 4.0? x4 from CPU (lanes 16-19) (unpopulated slot)
• Riser PCIe 3.0 x4 from PCH (lanes ?-?)
• 2.5" SATA 6Gb/s from PCH (lane ?)
• unpopulated SATA2 from PCH (lane ?)
• LAN PCIe 3.0 x1 from PCH (lane ?)
• Wifi PCIe 3.0 x1 from PCH (lane ?)
• WWAN PCIe 3.0 x1 from PCH (lane ?)

P350/M90q gen 2 has the NVMe slots connected to the CPU instead of the PCH, for PCIe 4.0 support (Q570 itself doesn’t support PCIe 4.0, 11th gen CPUs do).
Tiny7 is pretty awesome for SSD bandwidth, especially if you solder the 3rd slot.

Tiny8:

NM-D581 Rev 0.5 prototype board:

• DMI 4.0 x8 from CPU to PCH (Q670 ES)
• Riser PCIe ?.0 x8 from CPU (lanes 8-15)

Tiny9:

P3 Tiny and M90q gen 4 (NM-E881):

• DMI 4.0 x8 from CPU to PCH (Q670)
• Riser PCIe 4.0 x8 from CPU (lanes 0-7)
• SSD1 PCIe 4.0 x4 from PCH (lanes 21-24/25-28?)
• SSD2 PCIe 4.0 x4 from PCH (lanes 21-24/25-28?)
• Riser PCIe ?.0 x4 from PCH (lanes ?-?)
• 2.5" SATA 6Gb/s from PCH (lane ?)
• unpopulated SATA2 from PCH (lane ?)
• LAN PCIe ?.0 x1 fro PCH (lane ?)
• Wifi PCIe 3.0 x1 from PCH (lane 8)
• WWAN PCIe ?.0 x1 from PCH (lane ?)

!! Help requested: If you have a machine not (completely) listed here running Windows, a screenshot of Device Manager in ‘Devices by connection’ mode or HWINFO showing all the PCIe devices and associated root ports would be very helpful for documenting this across all generations. (better to have as many slots populated as possible for this)

NEC rebrands

todo

Known prototype boards

Parts links with hi-res images

Dell Optiplex Micro/MFF and Precision Compact/CFF

README 内容过长，已截取部分内容。完整内容请前往 GitHub 仓库查看。