Hi,
my softsynth realtime arranger setups up consist of the following

Option A.
Digital Piano as controller & for playing piano melody voices
512mb , 3.06 ghz Dell Laptop
Audigy 2 NX USB Soundcard ( for loading soundfonts)
Various Banks of GM soundfonts plus assortment of synthesizer soundfonts.
OMB Realtime arranger software
Jammer Live software
BIAB software etc

Option B
as above excluding the Audigy NX 2
instead I use the following software option

Brainspawn Forte http://www.brainspawn.com/products/forte/

Maple Virtual Midi Cable http://www.hurchalla.com/Maple_driver.html

Sounfont Player
LiveSynth Pro N/A
options http://www.rgcaudio.com/sfz.htm http://www.rgcaudio.com/sfz.htm

ASio4All asio driver http://www.asio4all.com/

best wishes
Rikki

p.s.
I have a newer dell duo core laptop with Audigy software inbuilt. Haven't totally sorted out all the snags yet, currently I'm using it for BIAB & loading sounfonts directly.

Nice overview.
This is what's active at the moment in my home

Kurzweil K 2600S
Acces Virus C
Machine drum
Roland R8M
Roland G 800
Clavia Nordlead Rack
Akai AX60
Akai S612
Digitech Studio Vocalist
E-magic Unitor 8
Spirit Folio SX mixer

Integrated thru PC pentium III 500 (to be replaced soon...by ????? )
software used;
Sonar
BIB
Sounddiver
CoolEditPro

I do have other boards like the VR760, but I use those live in the band on stage..

Fred