This is my 2004 Toshiba laptop. I can use Sonar 8.5 32 bit for live recording of up to 14 audio tracks. The only issue is screen re draw of wave forms takes forever after you stop the transport.
I'm not sure if you have run the DPCLAT monitor to make sure it is optimized correctly.
http://www.thesycon.de/deu/latency_check.shtml I use my Tascam us1641 and the older drivers. They released newer drivers for XP that were worse so I found using the originals that came on the CD best. I also get more stability using WDM mode. There's nothing wrong with WDM mode for a lot of tasks like audio recording and editing. Set you buffers way up there. This is not a machine for real time effects like Guitar rig.
I mostly have only used it to record our band and a few live concerts I was asked to do. I then transfer the files to my desktop. But I also muck about with downloaded midi files because my desktop is not on the internet so I can see if they are worth keeping using TTs-1 for playback.
I also refer to 8.5 when helping on the forum.
I can load up a MIDI file and simple synths like TTS-1 and Session Drummer. and work on stuff using just the on board Sound Max in MME mode.
It's all about optimizing the machine and it will work. But don't expect to load up a bunch of memory hog VST's. The older synths 32 bit synths seem fine, Stay away from Dim Pro and V vocal.