Power supply unit Dell RU199 305W ATX internal replacement for compatible Dell systems

The Dell RU199 305W ATX internal power supply is a replacement unit designed for compatible Dell desktop systems that require a 305-watt internal PSU in an ATX form factor. It delivers regulated DC voltages to motherboard, CPU, storage drives and peripherals via standard ATX connectors, providing stable power for routine computing tasks and system recovery. The unit is intended for repair or restoration of systems originally fitted with similar Dell power supplies and fits desktop enclosures that accept ATX internal power modules.

Advantages

This Dell-compatible internal power supply offers a defined 305W continuous output suitable for typical office and home desktop configurations. It supports the common ATX connector layout for easy installation and replacement in compatible chassis. Built to meet OEM-level compatibility expectations, the unit provides standard protections and stable voltage rails to help maintain system reliability when replacing a failed or aging PSU.

Suitable for

• Repairing or restoring compatible Dell desktop PCs that originally used a 305W ATX power supply
• Replacing a failed internal power supply in office workstations
• Upgrading a system with the same form factor and connector requirements
• Basic home or small-business desktops running standard HDD/SSD, single CPU and integrated or low-power discrete graphics

Key specifications

• Output power: 305 watts continuous
• Form factor: internal ATX power supply
• Connector types: standard ATX motherboard connector and peripheral SATA/Molex connectors (as required by compatible systems)
• Voltage rails: regulated multi-rail outputs appropriate for typical desktop components
• Cooling: internal fan for thermal management
• Mounting: fits standard ATX mounting points in compatible Dell desktop enclosures

How to use

Before installation, disconnect the computer from mains power and ground yourself to prevent electrostatic discharge. Open the desktop enclosure according to the system service instructions, remove the existing power supply if present, and note cable routing and connector positions. Mount the replacement ATX unit into the PSU bay using the appropriate screws, connect the 24-pin ATX motherboard connector and any required CPU, SATA or peripheral connectors, and ensure cables are secured away from fans and moving parts. Close the chassis, reconnect mains power, and power on the system to verify normal boot and component operation.

Recommendations

Use this power supply only in systems that accept a 305W ATX internal PSU and have compatible connectors and mounting. Verify connector types and available wattage requirements of installed components before replacement. If the system uses high-power discrete graphics or multiple drives, confirm total system power draw does not exceed the 305W rating. For safety, always follow manufacturer service guides and, if unsure, consult a qualified technician for installation.