Sony VAIO P core CM5 modding guide

This is where the VAIO P project stopped being an idea and became a packaging problem. We opened the donor, laid out every part, measured the useful spaces, and started turning those measurements into replacement board shapes.

Start with the VAIO P CM5 overview for the project hub.

Donor machine

Our donor is a Japanese-market VAIO P that still boots Windows 7. It is in good condition, which made the teardown feel a little more serious. The shell, keyboard, display, battery bay, and side openings all need to survive the experiment.

The old computer is expendable. The body is the reason for doing this at all.

Teardown approach

The first rule of this teardown was simple: do not pull until we know what is still attached. Flat-flex cables disappear under boards, fold around posts, and reappear at the side I/O and storage assemblies. A part can look loose while a delicate cable is still doing all the holding.

The side I/O was the most useful discovery. Sony did not force the power jack, USB ports, and headphone jack onto one large motherboard. It used small boards that fold and stack into the edges of the shell. Our replacement is likely to follow that pattern rather than pretending one large rectangle will fit.

Sony VAIO P disassembled parts laid out for Raspberry Pi CM5 carrier-board planning — The full parts layout shows the real problem: shell pieces, battery, LCD assembly, keyboard plate, side boards, ribbon cables, screws, and the original motherboard all compete for the same tiny volume.

Blue printed PCB mockups placed inside the Sony VAIO P lower shell for CM5 carrier and side-board fit checks — Printed board mockups make the CM5 carrier, LCD board, I/O board, and side boards physical before the PCB order. This is where connector placement and shell clearance become obvious.

Measurements

These are our first-pass dimensions from calipers, reference photos, and 3D scans. They are design constraints, not final fabrication numbers.

Part or bay	Measurement	Why it matters
Main chassis bay	133.4 mm	Total horizontal room available for the replacement mainboard area.
Original motherboard envelope	65.4 x 74.8 x 6.9 mm	Reference volume for the original compute electronics.
Outer shell envelope	244.37 x 123.94 x 13.96 mm	Overall bounding box from 3D scans.
Side-I/O assembly	99.0 mm span	Space used by the original peripheral-port strip.
Port pocket	41.5 mm span	Bracket area available for the USB stack and power input.

Carrier-board plan

We are designing around a Raspberry Pi CM5 Wireless 4GB Lite. Because this module has no eMMC, boot storage has to live elsewhere. An SD slot on an I/O board is the simple option. NVMe on the carrier is faster but takes more room.

The current layout breaks the computer into six boards:

carrier board
I/O board
LCD board
right-hand side board
left-hand side board
battery board

The left and right boards replace Sony’s original side modules. This lets us add modern ports such as USB-C while keeping them aligned with the factory openings.

Digital caliper measuring a side port pocket inside the Sony VAIO P lower chassis — A nominal board dimension is not enough. We also measured the port pockets and the height above the original side boards, because a connector that misses the shell opening by a millimeter is still a failed design.

Printed fit checks

Before ordering real PCBs, we printed the board outlines at 1:1 scale. The mockups are cheap, quick to revise, and surprisingly good at exposing bad connector positions. A3.8.5, Rev H, and A10 are snapshots along that fit-check path, not polished release names.

That is the lesson from this stage: PCB design here is mechanical design. The circuit can be electrically perfect and still fail if a cable cannot bend or the shell will not close.