Limitations in Graphs?

[jdommasc]

Hi ,
i have a problem with a Graph.
Iam trying to put all Fanspeed values of a Dell 1750 into one graph using lines.
The problem is everytime i tried to assign the datasource to the graph all looks well fan 1-7 were assigned to a graph datasource item. But after saving it 1-4 keeping assigned and 5-7 are filled with fan 4.
Thanks
Jens