GA-7N400-L Ram and USB problems

Hi

I'll get right to it ... I had 1 gig of ram (Kingston 2x512 meg DS
PC-3200) and went out and bought 2 more Kingston 2x512 meg SS PC-3200.
Placed them in order in which the manual told me to dealing with DS and
SS ... Anyways with all 4 Dimm slots filled the computer will boot and
will read 2 gigs yet won't go to the XP start up screen. It just kind
of hangs. If I take out the last one (DIMM 4) It will work fine, no
problems. I tired changing voltage to +1 and +2 and still with all 4 no
go. I have tested all 4 pieces of Ram and they all work perfect alone. I
have both SP 1 and 2 updates. Also have the latest in Bios updates F11.
So Where to now?
Also i installed a new harddrive and now all my usb ports are reading
1.1 when they should all be 2.0. I uninstalled them in hopes on a
reboot it will pick it up but no go. I also Downloaded USB 2 stuff from
the gigibyte web site but no dice. Same error all the time "This USB
device can perform faster if you connect to a USB 2.0 port click here
for the list of open ports" and i go there and well its all my ports
that are open anyways ... BLAH BLAH BLAH.
Anyways if anyone has any advice that would be great!
Thanx


--
Eyezie