Grouping and performance issues, can any duplicate this issue?

To get straight to it.. I am currently 5 boxing Rift on a single system across 3 monitors. I don't believe the system spec make a difference but for those interested I7 920, 12gb, Ati 5870, 40gp SSD, triplehead2go with 3 19" lcds running 3840x1024. So i started off adding one character at a time with good results. By the time I got to all 5 characters and updated ISboxer to select cpu affinities I still was pleasantly surprised at the performance.

With all characters logged in I commenced to fine tune the video setting to get a good balance. Without having to select "low quality renderer" I finally came up with slaves on Min setting and main with Medium setting. The main at this point was running about 45-50 fps (isboxer cap set to 50) and the slaves at 20fps (isboxer cap set to 20). I ran into a few rifts to test it and out and joined the rift groups via the raid component and after and hour or so I determined that this was going to work fine.

At this point I figured it was time to start questing and start the leveling grind. So I leave the rift group and form up my own group. To my shock each time I added an additional character my FPS dropped by about 5 fps. At the point where I had all 5 character in my group my main had dropped from 45-50 fps to 18-22. My first thought was that with all the added party frames it was causing my system to bog down. I then started removing all the party frames from all the slaves. I ended up making my slaves as minimalistic as possible (removing mini map, party frames, pet frames so on so forth) without any changes to my performance.

has anyone else out there run into a similar problem? or can anyone duplicate this issue? I am currently at a loss. The only workaround I came up with was to join a rift group and as everyone leaves it just reform the group and make it private. This way i can still have a small health bar on the screen and get the performance I want.. I checked on several mobs and being in a raid group doesn't seem to affect the xp at all so I may have to leave it as is until the problem can be resolved.

Thanks for listening

Unfortunately, it seems like Rift is a bit labile in terms of performance. One day, I get 55-60fps/30fps in a certain area and the next I get 14/12. If you are consistently seeing this drop when adding group members, I'll try to duplicate it for you (right now everyone joins at once heh).