A motherboard design changes during its life. Each change gets a new revision: parts are added or removed, values adjusted, components moved, problems fixed. The revision printed on your board tells you which version you hold, and therefore which schematic, boardview and BIOS files fit it best.
How revisions are written
| Designer | Where | Example |
|---|---|---|
| Compal, LCFC | After the board code | LA-D312P REV 1.0 |
| Dell (with Compal) | Build stage added | REV 1.0 (A00) |
| Quanta | Letter inside the part number | DA0R63MB6F1 = revision F |
| Inventec | Suffix | 6050A2412601-MB-A02 |
| Wistron | Digit after the project number | 16820-1 |
| Asus | After the model | X540MB REV 2.0 |
| Desktop boards | Near the model name | REV 1.1 |
Early engineering revisions (0.1–0.3) are rarely found in shops but their schematics often circulate. Version 1.0 is usually the first production design; later numbers mark production changes.
What changes between revisions
- component values and populated options;
- second-source parts with different packages;
- component positions — the biggest issue for boardviews;
- occasionally circuit fixes, such as an added capacitor or a changed enable path.
Working with a different revision
A close revision is usually fine for understanding how a circuit works and which signals control which rails. It is not reliable for exact component values or for finding parts by position. Confirm each part on the board before probing or heating it, and read the change history page at the end of the schematic when one is included. The practical method is in How to Match a Boardview to Your Board Revision.
Always record it
Write the revision next to the board code in every job note: "NM-A841 Rev 1.0", "DA0R63MB6F1 (rev F)". It makes the next search faster and explains any differences you notice between the files and the board.
Revisions and BIOS files
Firmware can depend on the revision too. A BIOS or EC image from a later revision may expect hardware an earlier board lacks, so when a board page lists several BIOS files, prefer the one whose revision matches yours — and always keep a backup of the original chip before writing anything.