RJ290 / PJ479 / X7841 / UG982 / XG312 – Motherboard for OptiPlex GX520 DT
Description
This GX520 DT motherboard (part numbers RJ290, PJ479, X7841, UG982, and XG312) is a genuine OEM desktop mainboard based on the Intel 945G chipset with the ICH7 southbridge. It supports LGA775 processors and DDR2 memory, offering a blend of reliability and legacy connectivity. Designed for the OptiPlex GX520 DT form factor, it is ideal as a direct replacement board or for system rebuilds requiring native support for older hardware and interfaces.
Technical Specifications
- Model Compatibility: GX520 DT form factor
- Part Numbers: RJ290, PJ479, X7841, UG982, XG312D
- Chipset: Intel 945G (northbridge) + ICH7 (southbridge)
- Processor Socket: LGA775 (Socket T)
- Supported CPUs: Intel Pentium 4, Pentium D, and Celeron D processors
- Front Side Bus: 533 / 800 MHz
- Memory Type: DDR2 SDRAM (dual-channel)
- Memory Slots: 2 × 240-pin DDR2 DIMM sockets
- Supported Speeds: DDR2-400 / DDR2-533 / DDR2-667
- Maximum Memory: 4 GB (2 × 2 GB)
- Graphics: Integrated Intel GMA 950 with VGA output
- Audio: Integrated high-definition 3-channel audio
- LAN: Integrated Gigabit Ethernet (RJ-45)
- BIOS: Phoenix BIOS
Rear I/O Ports
- 1 × VGA (15-pin D-Sub)
- 1 × Parallel port (DB25)
- 1 × Serial port (DB9)
- 1 × RJ-45 Gigabit Ethernet port
- 6 × USB 2.0 ports (arranged as three stacked pairs)
- 3 × 3.5 mm audio jacks — Line-In, Line-Out, and Microphone
Internal Connectors & Slots
- 1 × 24-pin ATX main power connector
- 1 × 4-pin 12 V CPU power connector
- 1 × CPU fan header (4-pin)
- 1 × System fan header (3-pin)
- 2 × DDR2 DIMM slots
- 1 × IDE/PATA connector (40-pin, labeled “DSKT”)
- 1 × SATA connector (blue, SATA 1.5 Gb/s)
- 2 × PCI expansion slots (32-bit, 33 MHz, white)
- 1 × Front-panel header (power/LED/reset)
- 1 × Front USB header (supports two ports)
- 1 × Front audio header (AC’97 / HD Audio)
- 1 × Speaker header
- 1 × CMOS battery holder (CR2032)
Form Factor & Compatibility
- Form Factor: MicroATX (approximately 9.6" × 9.6")
- Case Compatibility: GX520 Desktop (DT) chassis only
- Power Supply Compatibility: Standard 24-pin ATX DT power supply
☑️ Key Features
- ☑️ Integrated Intel GMA 950 graphics for reliable video output
- ☑️ Dual DDR2 memory support up to 4 GB
- ☑️ Onboard Gigabit LAN for network-ready operation
- ☑️ Dual PCI expansion slots for additional cards
- ☑️ Full legacy I/O support including parallel and serial ports
- ☑️ 6 × rear USB 2.0 ports for modern peripherals
⚙️ Fit Notes
- Compatible only with GX520 DT chassis; not suitable for SFF or MT variants.
- Use non-ECC DDR2 memory modules.
- Ensure correct connection of the front-panel and USB headers during installation.
- Apply Shin-Etsu G751 Thermal Grease when installing or reseating the CPU.
