Since quite a few battle.net updates ago my Diablo 3 has been lagging more then usual, but i haven't given it much thought until now.
When i loaded up my resource monitor to see what was causing the lag, i noticed that my services were using up almost as much CPU as d3 was, specifically the SSDP Discovery service. I did some googling, and after deciding i did not need this service, i disabled it and restarted my computer.
After starting d3, a new service started using the exact same amount of resources, named Seclogon or Secondary Logon service. After disabling this one too, i got stuck at "Updating Blizzard Update Agent" when attempting to start D3. I found users having similar problems on the forums, so i followed the instructions, and checked that my Agent and CLient versions were current; they were. I deleted the battle.net folder from my prgmdata folder, and after the launcher replaced the folder, it got hung up on the same "Updating Blizzard Update Agent" message again.
So i re-enabled seclogon and restarted again. D3 launched just fine this time, but i am still looking at 40% of my CPU going to this service every time i tab into Diablo. It only uses 10% or so if i am tabed out of D3, or if i am logged out of Bnet. When D3 is not running, these processes use nothing.
Is this normal? I am using an AMD dualcore CPU, a gigabyte mobo, and a Nvidia 260ish GPU. I would be more then happy to give you any other information, please ask for what you need!