• Status: Draft for review
• Product: Dockable handheld gaming PC prototype with integrated controls.
• Performance target: Comparable to the Radxa X4 / Intel N100 class.
• Primary differentiator: One full-featured, recessed USB-C port used for charging, dock insertion, DisplayPort video, USB peripherals, and controlled power output.

• Portable play for lighter PC games such as Minecraft and Roblox.
• Steam Deck-style integrated controls and grips.
• Desktop/TV use through a Switch-style drop-in USB-C dock.
• Prototype platform for Windows, Linux, and development of a custom operating system.

• Run x86-64 Windows and Linux; allow dual boot from NVMe.
• Boot a future custom OS through standard UEFI.
• Provide integrated gamepad controls, touchscreen display, speakers, Wi-Fi, Bluetooth, battery operation, and active cooling.
• Approach five hours of runtime in a constrained light-gaming profile.
• Dock through the normal USB-C port for charging, video, USB expansion, and Ethernet.

• Sourceable x86 compute module, with ARM retained only as a fallback.
• 7.5–8-inch display; prototype preference is 1280×800 or similar at 60–90 Hz to reduce GPU and power load.
• 8 GB RAM minimum; 16 GB preferred.
• Replaceable M.2 2230 NVMe storage.
• Wi-Fi 6 and Bluetooth 5.x.
• Integrated sticks, D-pad, ABXY, shoulder/trigger controls, menu buttons, haptics, and optional rear buttons.
• Stereo speakers and 3.5 mm headset support.
• USB-C PD charging and docking.

Diagram

• Prototype baseline: LattePanda Mu N100, because it is sold in prototype quantities, includes LPDDR5/eMMC, supports Windows/Linux, and has public carrier-board design resources.
• Module size is approximately 69.6 × 60 mm and input range is 9–20 V.
• The carrier must use a BIOS-supported HSIO allocation. Any non-default lane assignment may require vendor BIOS customization.
• Industrial SMARC modules are a future production option but are larger/more expensive and may not use the exact N100 SKU.

• 7.5–8-inch landscape touchscreen.
• Target 1280×800-class resolution for the first prototype; 1920×1200 panels are available but increase rendering and backlight load.
• Internal interface should be eDP where supported by the compute module.
• Brightness target: approximately 400–500 nits.

• M.2 2230 NVMe, 256 GB minimum.
• On-module eMMC used for recovery, diagnostics, or bootloader development.

• Dedicated low-power MCU scans controls, handles haptics, battery/power-button events, fan policy assistance, and exposes a USB HID gamepad to the x86 host.
• Hall-effect sticks and analog triggers preferred.

• Recessed, mechanically guided USB-C receptacle on the bottom edge.
• Device operates as USB host for dock peripherals and emits DisplayPort Alt Mode video.
• Power role is dual-role: sink while charging/docked and limited source when powering supported peripherals.
• Prototype architecture uses a USB-C PD controller, a DP/USB crossbar mux or redriver, ESD/short-to-VBUS protection, and a bidirectional charger/power stage.
• Dock provides HDMI or DisplayPort, USB-A ports, Ethernet, and external PD input.

• 3S or 4S Li-ion/Li-polymer pack, 45–50 Wh.
• Bidirectional buck-boost charging/power path, fuel gauge, pack protection, cell balancing, and temperature sensing.
• 45 W USB-C adapter baseline; 60 W preferred for simultaneous operation and charging.

• Copper heat spreader plus compact blower and fin stack.
• Quiet profile targets 8–10 W total compute-module power; performance profile may exceed this and reduce runtime.

• Battery: 45–50 Wh nominal; design around approximately 90% usable energy after reserve and conversion losses.
• Target: Approximately five hours for Minecraft/Roblox only in an optimized low-power profile.
• Expected: Roughly 3–4 hours at normal brightness and less restrictive performance settings; heavier games will be shorter.
• Docked mode may raise processor limits while the dock supplies power.

Diagram

• A 50 Wh pack with about 45 Wh usable yields 5 h only at 9 W average.
• At 14 W average, expected runtime is about 3.2 h.
• The power path, battery, connector, and protection should support at least 45 W continuous and processor/charging transients with margin.

• One-off proof-of-concept followed by a smaller integrated prototype.
• First electronics revision should be a carrier/bring-up board, not a fully miniaturized final motherboard.
• High-speed carrier likely requires at least 6 layers; final handheld may require 8 layers depending fan-out and interface density.
• Use controlled impedance for USB 3.x, DisplayPort/eDP, and PCIe.
• Battery pack should be purchased as a protected, certified custom/OEM pack rather than assembled from loose pouch cells for the first prototype.

• Standard UEFI with selectable boot entries and removable NVMe.
• Recovery path using on-module eMMC or external programmer access.
• Controller MCU firmware update over USB or SWD.
• Expose serial/debug header for early custom-OS work.
• Avoid undocumented custom peripherals where possible; select USB HID, standard I2C, PCIe/NVMe, HDA/I2S, and eDP interfaces.

• Integrated Steam Deck-style grips and controls.
• Target mass: 600–650 g.
• Target display: 7.5–8 inches.
• Split battery placement to balance weight across both grips/rear shell where practical.
• Bottom USB-C port with tapered dock guides so insertion loads are transferred to the enclosure rather than the connector.
• Rear intake and top/rear exhaust must remain clear in handheld and docked operation.
• Provisional overall envelope: approximately 260–285 mm wide, 105–120 mm tall, and 25–35 mm maximum grip thickness.

• Use an x86 compute module for the prototype instead of designing directly around an Intel BGA processor.
• Prioritize LattePanda Mu N100 due to accessibility and open carrier references.
• Use the same USB-C receptacle for portable charging and dock insertion.
• Optimize the first display for power/performance rather than maximum pixel count.
• Build the product in phases: industrial/mechanical concept, compute-module bring-up, integrated carrier, controller boards, dock, then enclosure refinement and custom OS.

• Five-hour runtime is a low-power-profile goal, not a guarantee across all games.
• The custom OS will initially rely on UEFI and standard PC hardware interfaces.
• The first dock does not include an external GPU.
• USB data role remains host; “dual role” primarily refers to USB-C power role and docking behavior.
• Exact display, battery pack, controls, and enclosure geometry remain provisional until sample parts are acquired and measured.

• Initial specification created from the product brainstorming and feasibility research.
• Added full-featured USB-C dock requirement, dual-boot/custom-OS support, 600–650 g target, and five-hour light-gaming objective.