If the system will not boot or BIOS settings are forgotten, you can reset the CMOS:
The motherboard is a proprietary LGA 1155 board primarily used in the ThinkCentre M92p and M82 desktop series. Because it is a proprietary OEM part, a standalone "motherboard-only" manual does not exist; instead, all technical details are found in the system-wide Hardware Maintenance Manual (HMM) and User Guide . Official Documentation lenovo is7xm rev 10 motherboard manual
LGA 1155 (supports 2nd and 3rd Gen Intel Core processors). Memory: 4x DIMM slots supporting up to 32 GB DDR3 . Storage: 4x SATA III (6.0 Gb/s) connectors. Audio: Realtek ALC662 6-channel High Definition audio. Networking: Integrated Gigabit LAN. Critical Connectors & Pinouts As an OEM board, the Go to product viewer dialog for this item. If the system will not boot or BIOS
4x 240-pin DDR3 DIMM slots, supporting up to 32GB of RAM. Expansion Slots: 1x PCI Express x16. 1x PCI Express x1. 2x PCI slots. Storage: 4x SATA III (6Gb/s) connectors. Critical Connector Pinouts Memory: 4x DIMM slots supporting up to 32 GB DDR3