I have 5GB, just looked online and it's somewhat confusing with the different system requirements, I see yours is a 2008, mine a 2007. One site has a scanner that you download and it tells you exactly what you need but who knows if it's safe to download. I definitely will get more ram though.
At some point in the near future is your computer not going to be able to run a newer OSX or did apple just decide the cut off woul end with the pre 2008 mac pros.I just checked apples site and pre 2008's can't even get mountain lion, I'm on snow leopard, at some point I'm not going to have the system requirements for some new software programs that will be coming to market.
Model Name: Mac Pro
Model Identifier: MacPro1,1
Processor Name: Dual-Core Intel Xeon
Processor Speed: 2.66 GHz
Number Of Processors: 2
Total Number Of Cores: 4
L2 Cache (per processor): 4 MB
Memory: 5 GB
Bus Speed: 1.33 GHz
Boot ROM Version: MP11.005C.B08
SMC Version (system): 1.7f10
Serial Number (system): G************PZ
Hardware UUID: 00000000-0000-1000-8000-0017F20D5E9A
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