Patches ESXi 5.0

Hi All

I installed Update manager. I wan to customize the downloading patches. Because we are using the esxi 5.0 and my update manger is downloding the patches for esx 3.0 4.0 also. I just want to download esxi 5.0 patces. how can we add the url for downloading the patches for esxi 5.0 ? how can we prevent the patched fo old version of esx or esxi not to download ?

Thanks in advance.