help with kernel panic please

Hi i bought a used powermac g5 and i was having frequent kernel panics .i never had a mac before so i didnt even know it was a kernel panic at first eventually i noticed it happened alot when using bittoreent or something like it i then got the leopard upgrade and stopped using any torrent software at all and everything was fine until today i got about two kernel panics...can someone please help me...this is what i got.

Interval Since Last Panic Report: 1 sec
Panics Since Last Report: 1
Anonymous UUID: 631AB9DE-DEA1-4E8F-9FC1-74873BEDF776

Tue Oct 27 22:47:09 2009
panic(cpu 1 caller 0x002C7B30): "m_free: freeing an already freed mbuf"@/SourceCache/xnu/xnu-1228.15.4/bsd/kern/uipc_mbuf.c:3574
Latest stack backtrace for cpu 1:
Backtrace:
0x0009CC88 0x0009D63C 0x00029DA0 0x002C7B30 0x26BC03B4 0x27F161B8 0x27F1645C 0x27F16748
0x27F17F74 0x26BCC814 0x0035D794 0x26BCC924 0x26BCCC80 0x26BCD47C 0x26BC5994 0x0012F0E0
0x00161DA0 0x00168488 0x00169B84 0x00165FF4 0x00159CC8 0x0015C0A4 0x0015C19C 0x001461F4
0x0013208C 0x0012E50C 0x0012EBEC 0x0012EE88 0x000B1DD4
Kernel loadable modules in backtrace (with dependencies):
com.Ralink.driver.RT73(1.1.7)@0x27ef8000->0x27f30fff
dependency: com.apple.iokit.IOPCIFamily(2.6)@0x1e64c000
dependency: com.apple.iokit.IONetworkingFamily(1.6.1)@0x26bb5000
dependency: com.apple.iokit.IOUSBFamily(3.4.9)@0x269ce000
com.apple.iokit.IONetworkingFamily(1.6.1)@0x26bb5000->0x26bd3fff
Proceeding back via exception chain:
Exception state (sv=0x1e8e3a00)
PC=0x00000000; MSR=0x0000D030; DAR=0x00000000; DSISR=0x00000000; LR=0x00000000; R1=0x00000000; XCP=0x00000000 (Unknown)

BSD process name corresponding to current thread: kernel_task

Mac OS version:
9L31a

Kernel version:
Darwin Kernel Version 9.8.0: Wed Jul 15 16:57:01 PDT 2009; root:xnu-1228.15.4~1/RELEASE_PPC
System model name: PowerMac7,3

System uptime in nanoseconds: 1357471142689
unloaded kexts:
com.apple.driver.Apple02DBDMAAudio 2.5.8f1 - last unloaded 4158091445
loaded kexts:
com.Ralink.driver.RT73 1.1.7 - last loaded 15155227922
com.paceap.kext.pacesupport.leopard 5.7
com.apple.driver.AppleTopazAudio 2.5.8f1
com.apple.driver.AppleTAS3004Audio 2.5.8f1
com.apple.filesystems.autofs 2.0.2
com.apple.driver.DiskImages 199
com.apple.driver.AppleFCU 1.3.2b0
com.apple.driver.AppleK2Fan 1.0.10f1
com.apple.driver.AudioIPCDriver 1.0.6
com.apple.driver.AppleSlewClock 1.5.2d0
com.apple.driver.AppleHWSensor 1.9d0
com.apple.iokit.IOFireWireIP 1.7.7
com.apple.driver.AppleLM7x 1.9d0
com.apple.iokit.AppleGMACEthernet 1.5.9f1
com.apple.driver.AppleCPUVoltage 1.5.2d0
com.apple.ATIRadeon9700 5.4.8
com.apple.driver.AppleUSBAudio 2.6.4b17
com.apple.driver.AppleK2Driver 1.7.2f1
com.apple.driver.PowerMac7_2_PlatformPlugin 3.4.0d0
com.apple.driver.AppleMaxim6690 1.9d0
com.apple.driver.AppleI2S 1.0.1f1
com.apple.driver.AppleAD741x 1.9d0
com.apple.driver.AppleHIDKeyboard 1.0.9b4
com.apple.driver.AppleUSBMergeNub 3.4.6
com.apple.iokit.IOSCSIMultimediaCommandsDevice 2.1.1
com.apple.iokit.SCSITaskUserClient 2.1.1
com.apple.driver.XsanFilter 2.7.91
com.apple.iokit.IOATABlockStorage 2.0.6
com.apple.driver.AppleUSBHub 3.4.9
com.apple.iokit.IOATAPIProtocolTransport 1.5.3
com.apple.iokit.IOUSBUserClient 3.4.9
com.apple.driver.ApplePMU 2.5.6d2
com.apple.driver.AppleK2SATA 1.0.4f2
com.apple.driver.AppleGPIO 1.3.0d0
com.apple.driver.AppleVIA 1.5.1d1
com.apple.driver.MacIOGPIO 1.3.0d0
com.apple.driver.AppleMPIC 1.5.3
com.apple.driver.AppleI2C 4.0.0d2
com.apple.driver.

 

2.3 ghz processor
1 gb ram.
i have a belkin wireless little usb thing hooked up for my wireless internent.
and i am using a m-audio mobile-pre to hook up my studio speakers through usb.
I have a oxygen 49 keyboard through usb not midi,
and my normal stock keyboard hooked up through usb,

the computer comes with three build in firewire ports but i dont use them.

...i notice it happens alot when downloading a torrent...maybe it does have to do with the enternet.

 

i have unplugged and replugged the usbs several times.....i get the panics just ramdomly...i notice there either when im on the enternet or im downloading a torrent...

 

how do i disconnect peripherals?
and would u be able to send me a link for that airport extreme module i been wanting to buy a new wireless thing mine is real cheap.... soo u think it has to do with something hooked up through usb...cus im ready to go out and get some new ram someone told me it might be the ram card..

and i appreciate everyones help im real new to this and i decided to ask the people that really know what there talking bout...thanks alot guys

 

ok i appreciate everything man im guna look for a new thing to connect to the internet ...do u recommend any devices that would connect me to wireless enternet.? and about the ram im gunna buy some more ram anywayz if anything ill compare my old and my new

 

i appreciate everything man