Double Trouble with Vista Premium 64 Install

Hello all

Before my tale of woe I feel I should give you my spec.

*AMD Athlon 64 X2 Dual Core Processor 4200+ (2 CPUs), ~2.2GHz *

*2x XFX Geforce 8600 GT 512mb in SLi mode*

*Creative X-fi extreme audio card*

*3072mb DDR 400 (2x 512) & (2x 1gb) RAM*

*ASUS A8N32 - SLi Deluxe Mobo.*

*550 watt PSU.*

Ok,

Firstly I installed Vista 64 Premium over my previous OS, which was XP
Home edition.
I then replaced my 7600GT cards with XFX 8600 GT cards.

My first challenge I faced was that Vista did not recognise my creative
sound card was on board. Despite downloading the Vista driver from
Creative site, the driver wont install because it cannot find the
device.

Is there a driver I can manaully load through device manager?

(I have switched to onboard sound temporarily, Realtek 97 until I can
resolve this.)

Secondly, Vista is only recognising 1198mb of RAM. I have switched
the Dimms around but still no joy. Do you think there is a confliction
with the 512mb of DDR3 memory on each of the XFX cards? (a stab in the
dark guess.)

The bootup still recognises 3072mb of RAM.

Should I have formatted HD before installing Vista?

I really dont want to return to XP with my tail between my legs, so any
help you can offer would be very much appreciated!!


--
nirrum