On XP running DO 10.0.2.0, if I fire up a Remote Desktop (mstsc.exe) session then my computer becomes largely unusable. Both mstsc and dopus show very high cpu usage, about 50% and 30% respectively. If I kill dopus/dopusrt then mstsc's cpu usage returns back to its normal level (less than 5%) and the computer becomes usable again.
I've also noticed that if I start mstsc before dopus/dopusrt start then cpu usage across the board is normal. Sound like a bug?
It is a bug, but in the Windows XP RDP/TS software rather than Opus.
There are lots of different things that can cause it and Opus just happens to be the trigger in your case.
There a lots of threads about it from people who don't use Opus, and many of the threads suggest different solutions which worked for different people, so hopefully one will work for you:
google.co.uk/search?q=mstsc+cpu+usage
(I've seen a load more threads over the years, so other search terms may find more suggestions, but hopefully that's a good starting point. Luckily, Vista and above seem to have solved the problems like this.)
Disabling clipboard, sound, disk and USB device sharing in the RDP client is worth a quick try, also, if you don't need them (or just as a test).
Thanks very much Leo, appreciate the help.
there is a way to avoid this problem
before you run rdp client (the problem and the solution is also applicable for mRemote)
you need to kill opus (and dopusrt)
(i know it's desecration 
then rdp / mRemote works fine
and opus can be started as usual
i never noticed the problem when i applied what's above
i hope it will work for you also
br
pixel
geeez
jarmod wrote it above ))
sorry guys
Don't just kill Opus as it might be in the middle of writing config files out to disk.
Instead, exit it cleanly, either via the UI or via a batch file or script.
If you are able to consider an alternative to RDP, have a look at TeamViewer. I use TeamViewer Host (service) on the server and TeamViewer Portable on the client. I have never had any problems interacting with Opus or any other application.
Regards, AB
Or just stop using XP if you can, since the problem doesn't affect Vista and above and XP's days are numbered anyway.
I spend half my life in Win7 Remote Desktop sessions, using Opus as well of course.
(Of course, you don't always have a choice about XP at work. 
Roll on 2014!)
mRemote and RemoteDesktopManager rises the same issue
mRemote and RemoteDesktopManager don't look like alternatives to RDP; they seem to be UIs on top of RDP (and other clients like VNC).
Presumably, when using them in RDP mode, they are simply wrappers around the underlying RDP components/functionality in Windows (which on Windows XP includes the high-CPU clipboard bug that Opus, and lots of other things, can trigger). They wrap a nicer UI around those components but they don't change how the components themselves work.