OnLine 7.X performance - R U satisfied?

hi all, i have just installed 7.11 on a sprcserver 20 platform. my migration went well, and when i had about half the company on the system, (approx. 30-40 threads), and the system was running really well. i had it tuned for what i though would be a good approximate starting point, and that turned out to work really well. i've added the rest of the company, (approx. 70 - 80 threads), and now the system is much slower, much more so than i had hoped for by going from approx. 30 to approx 70 threads. so far there doesn't appear to be anything abnormal. my disk activity is realtively light, nothing seems to be hogging memory, my # or ready threads jumps between 2 and 6, my checkpoints are averaging 1 - 4 seconcds, things like this. it seems that this is going to be an interesting process. i have 2 physical cpu's but am running as a single cpu machine. the concensus from the net is anything less than 4 is better off as 1. i might give it a try, but later. my question is this: i've seen a number of posts complaining of installing 7.X and having the system slow down significantly from 5.X or whatever version that was running before. but i don't recall seeing posts about getting the system in tune, and having it run faster or better than before the upgrade. i guess that isn't really a question...:-) can people reply to this, if they have come to the point where they have tuned the system, and it is now running as we would expect, and what they did to get there? considering that i can't find any obvious bottlenecks, i would expect to be seeing at least similar performance to my 5.X system. curiously awaiting replies... mickm