The LA-E791P Rev 2.0 Schematic Diagram is more than a PDF file; it is the definitive reference for reviving dead motherboards. Without it, you are flying blind into a sea of tiny capacitors and black epoxy. With it, you can logically isolate whether your fault lies inside the charger IC, the VRM controller, or the Embedded Controller.
If you repair Dell laptops for a living, ensure you store the Rev 2.0 schematic alongside the Boardview file. Keep a copy on your repair bench tablet and another on your PC. The next time a Vostro 5471 comes in with a mysterious short, you will know exactly where to probe first.
Disclaimer: This article is for educational purposes. Schematics are copyrighted by Dell/Compal. Ensure you own the physical motherboard before downloading proprietary repair data.
LA-E791P Rev 2.0 motherboard (code-named CSL50/CSL52 ) is a high-performance laptop mainboard manufactured by Compal Electronics
laptop series. This guide provides a technical overview based on schematic data to assist with diagnostic and repair tasks. AliExpress Core System Architecture La-e791p Rev 2.0 Schematic Diagram
The board is designed around a unified "U-series" architecture, typically integrating the CPU and PCH into a single package to save space and power. CPU Support: Compatible with Intel Sky Lake-U (6th Gen) Kaby Lake-U (7th Gen)
processors, ranging from Celeron/Pentium up to Core i3/i5/i7 models (e.g., i3-6006U, i5-6200U).
Features two DDR4 SO-DIMM slots, though some variants may have integrated memory or a single slot. Most revisions use UMA (Integrated Intel Graphics) , but high-end versions can include an AMD R17M discrete GPU with dedicated DDR3L VRAM. AliExpress Key Schematic Sections
A complete schematic for the LA-E791P typically contains approximately 43 to 60 pages of technical data, including: Power Management Diagram: The LA-E791P Rev 2
Outlines the "Power Sequence" or how the board wakes up after the power button is pressed. Voltage Regulation Module (VRM): Details the power rails for the CPU core ( positive 1.2 cap V ), and system standby ( positive 3 cap V cap L cap P positive 5 cap V cap L cap P Peripheral Connectivity:
Schematics for SATA (Storage), PCIe (M.2/Wi-Fi), HDMI, USB 3.0, and Audio processing. Embedded Controller (EC):
The logic for keyboard, fan control, and battery charging is managed here. Troubleshooting & Power Rails
Common diagnostic points on this board involve checking the power passage through specific coils: Disclaimer: This article is for educational purposes
Confirm you want the full technical guide and I’ll produce the detailed walkthrough.
Look for the RAM power generation circuit.
If you are repairing this board, locate these specific pages in the PDF:
The "LA" prefix denotes a Compal motherboard design. The full identifier "LA-E791P" is silkscreened directly onto the PCB next to the RAM slots. The "Rev 2.0" is critical; Dell and Compal often release multiple revisions (Rev 1.0, 2.0, 3.0) with different component placements, resistor values, and IC pinouts. Using a Rev 1.0 schematic on a Rev 2.0 board will result in misdiagnosis.
Before you press the power button, you need +3.3V_ALW and +5V_ALW. The LA-E791P uses a TPS51225C (or similar) for this.