I have installed mac osx 10.5.4 but is there any possible way to upgrade it or a different install that will work? These are my specs

I have osx 10.5.4 installed on this setup but I need 10.5.5 or higher. Is there a distro that will work with this.

Specs

Motherboard description Motherboard manufacturer's name: ASUS A8M2N-LA
HP/Compaq name: NodusM3-GL8E

CPU/Processor Socket: AM2
Supports AMD Athlon 64, Athlon 64 X2, and Sempron processors

Front-side bus (FSB) 2000 MegaTransfers/second

Chipset GeForce 6150 LE chipset

BIOS features Award brand system BIOS
Keyboard combination to used to enter BIOS: F1

Form factor Micro-ATX: 9.6 in X 9.6 in

Memory Four 240-pin DDR2 DIMM sockets
Supports PC 4200 (533 MHz) and PC2 5300 (667 MHz) DDR2 DIMMs
non-ECC memory only, unbuffered
Maximum HP/Compaq approved memory is 4 GB*



NOTE: *Actual available memory may be less

Expansion slots Three PCI
One PCI Express x16 graphics

Video graphics Integrated

Serial ATA 4 SATA connectors
Each connector supports 1 serial ATA-150 disk drive

Onboard audio Built-in High Definition 8 channel audio
ALC888 CODEC
Onboard LAN 10/100 Marvell 88EC031

Back panel I/0 Listed in physical order from left to right:
One PS/2 keyboard port (purple)
One PS/2 mouse port (green)
One SPDIF (coaxial) out
One VGA port
One IEEE 1394
Four USB 2.0
One RJ-45 networking port
Audio ports:
side speaker out (gray)
rear speaker out (black)
center/subwoofer (yellow orange)
line in (light blue)
line out (lime)
microphone (pink)

Internal connectors One 24-pin ATX power connector
One 4-pin ATX power connector
Two PATA connectors
Four SATA connectors
One floppy drive connector
Two 12v fan connectors for CPU fan and PC fan
One 9-pin header for power button, reset button, power LED, and HDD LED
One audio header for headphone-out and microphone-in
One audio header for line input
Two USB 2.0 connectors supporting 4 additional USB 2.0 ports
One IEEE 1394 connector