Server Monitoring Tools

Hey guys,

I’m looking for a server monitoring tools, that gives real time alerts and reporting on CPU, Disk Space, memory usage..

I have have a great program called UPtime but it’s a bit out of our budget and i’ve looked at Big Brother by Quest and it does not do everything i would like.

Does anyone know of any other server monitoring out there that gives

-RealTime monitoring
-Detailed Reporting on CPU/Disk/memory

Were running Windows 2003 Server on IBM Servers.