Not sure if your client has given up. We used to have issues with eRx taking an excessive amount of time but everyone had that. I have NEVER heard of anyone having this much time with opening a chart. I doubt it is the server. I doubt it is AC. You have good SSDs and plenty of RAM on the PCs.
If we could know:
Speed of switch
Wired or wireless
Speed when connected by Ethernet cable directly to server. Just get a 50 to 100 foot Cat6 cable.
SQL is blazing fast when compared with AC so it won't be that.
Remember, no one else I have ever heard of has had an issue like this. I could see changing EMRs if it were this slow. I can almost guarantee you it is not AC. You are simply connecting to SQL.
It could very well be your network.
