[LAU] ubuntu 9.10 RT and Jack

I've asked about this on the ubuntu forums to little avail...just wondering what you guys might think. Far from a professor of linux audio, but I'm getting more and more into it. I've built a couple basic machines from scratch recently, amd dual cores w/ 2gb of memory. Not wanting to spend the extra dough on a nice sound card + interface yet, I settle with just using chipset sound. The 9.10 and 9.04 vanilla kernels have worked for me pretty well using Jack, but if I whenever I try to get the RT working, all kinds of problems show up: insane amounts of Xruns just as Jack starts up, Ardour can't connect, and processor ends up using half its resources to stay running. Needless to say, recording is not really possible. This is after tweaking memlocks, nice %s , buffers and so on. I know that chipset sound, is not a very efficient recording interface, but it seems there is more going on, besides that. I have two main questions here (they sum up to: how much of this is the chipset?) a. i had heard here and there in forums that the RT kernel in 9.04 and on was 'broken'. is that true? b. Is RT only worth using for higher end machines with more ram and separate sound cards? And one more: Would anyone recommend using a different audio OS for this situation, like 64 studio? (i might have mentioned jacklab, but it seems that project has been killed) Im hoping someone can help settle my curiosity here......