A tua placa tem estas caracteristicas:
CPU
• Support Socket 478 for Intel® 4 (Socket 478) Processor.
• CPU Supports 1.3GHz to 2.2GHz and up.
Chipset
Intel® 845 chipset. (593 FC-BGA)
• AGP 4X slot (1.5v only)
• 400MHz Intel NetBurst micro-architecture bus.
• Support 100MHz FSB.
Intel® ICH2 chipset. (360 BGA)
• AC97 Controller Integrated.
• 2 full IDE channels, up to ATA100.
• Low pin count interface for SIO.
Main Memory
• Two 184-pin DDR DIMM sockets.
• Max. Memory size: 2GB.
Slots
• One CNR (Communication Network Riser).
• One AGP 4X slot (1.5v only)
• Six PCI 2.2 32-bit Master PCI bus slots.
• Supports 3.3v/5v PCI bus interface.
On-board IDE
• An IDE controller on ICH2 provides IDE HDD/CD-ROM with PIO, Bus Master and Ultra DMA 66/100 operation modes.
• Can connect up to four IDE devices.
On-Board Peripherals
• 1 Floppy port supports 2 FDD with 360K, 720K, 1.2M, 1.44M and 2.88Mbytes.
• 2 serial ports (COM A + COM B)
• 1 parallel port supports SPP/EPP/ECP mode
• PS/2 keyboard/mouse connector.
• 4 USB ports (Rear x2 / Front x2).
• 1 Line-In/Line-Out/Mic-In/Game port.
Audio
• ICH2 chip integrated
• AC'97 codec supports 2 channel audio
BIOS
• The mainboard BIOS provides "Plug & Play" BIOS which detects the peripheral devices and expansion cards of the board automatically.
• The mainboard provides a Desktop Management Interface (DMI) function which records your mainboard specifications.
Dimensions
ATX Form Factor.
Não te respondi bem , ou seja poder meter uma placa agp8x podes agora o rendimento em teoria não será o ideal, porque serão protocolos diferentes, não utilizará a placa em pleno.