Its not the chip only. Its the chip, the DACs and the opamps that work together to produce the sound. Check online forums, I think you'll find that they say the Elite Pro is better then the titanium and the PCIe slot makes no difference. Heres one example, but there are bound to be plenty more (which I can find for you if you like):
http://hardforum.com/showthread.php?t=1468745
Your first priority should be to buy Z5500 or equivalent speakers. They have to be atleast THX certified
http://hardforum.com/showthread.php?t=1468745
Your first priority should be to buy Z5500 or equivalent speakers. They have to be atleast THX certified