I have 8.1 Select running under WinXP,on Quad Opteron with 4GB of RAMand QuaddroFX4500. Ot was workinggreatandblindding fast. Then allof a sudden for no reason, I can think off, its GUIspeed went to toilet. There is a 10-20 second delay between adding nodes, even in empty scenes. TheGUI freezesfor 10 seconds when I draw a curve in Geometry. It takes 30 seconds to switch from Objects to Geometry. I have reinstalled 8.1 from build 822 to 859 three times, with identical results. What could be the cause.

DaveR

It could be a number of things. Off the top of my head:
- Check the Task Manager to make sure you don't have some errant process that is taking up 100% of your CPU time.
- Have you changed video drivers recently?
- Try closing/minimizing all other windows (including MSN, Yahoo, etc.)
- Try closing as much as you on the system tray

No none of the above. The 2D display part of the houdini went bust, without warning. I've reinstalled the Nvidia drivers, reintalled the houdini. Nothing , no change. If anything its getting worse.

Letssay I have a new empty scene. In Geometry I lay down an Add SOP. It takes twenty seconds for the operation to complete. Thats insane. It used to be instanteneous. There were no changes to hardware, no new software. It simply started happening, and won't go away.

Something quite similar happened to me 2 or 3 times. If I have Houdini open and I start another program which also uses OpenGL (After Effects for example), then I close that other program and return to Houdini. It might happen that suddenly Houdini doesn't have OpenGL acceleration. But everything comes back to normal after a restart. (I have an Nvidia Geforce)
Maybe you have some resident software which is using OpenGL?

Dragos

This is a common problem for me on Linux. If I have two or three geometry heavy* Houdini sessions open, then open a third ‘empty’ Houdini session it appears to run all the OpenGL calls through the CPU and it takes 10 seconds to just draw the UI. This new Houdini session will remain that way until I close it. If I close one of the heavy scenes any new Houdini sessions I open will run fine.

*Even though the scenes are heavy I still have plenty of memory and the sessions are idle, (not chewing up CPU).