looping reboot after 3gigs on dragon2 v2 and XP

Soyo KT880 Dragon2 v.2, XP2900+

The board has 4 slots and supports 4G of memory

Windows XP Home

I took out 2 512 sticks from DimA 1 and DimB 1(as per the manual) and
replaced them with 3 GSkill PC3200 1G sticks in DimA 1, DimA 2 and DimB 1.
The BIOS sees all three and reports them in POST. Windows gets past the dual
boot selection but during the Windows startup splash (*not* the welcome
screen) the back-and-forth bar halts after only two passes and a blue screen
flashes faster than I can read (I *think* it says IRQ not less or Equal but
not following that with any specifics, but I'm not sure and don't want to
continually reboot it for fear of corrupting something) and the machine
reboots all the way back to POST.

I took out all but one stick and tried each one on it's own and each are
good to go. I put only two in (DimA 1 and DimB 1) and she runs fine. I then
put the two 512 sticks in the other slots and it POSTs OK reporting 3G in
128bit mode, but XP failed as before.

The three one gig sticks are these:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231047


This machine is *not* set to automatically restart on errors, but it just
flashes a blue screen too fast to read and reboots anyhow.

I see nothing in the event viewer that is any different than any other day
and *no* event log is created during the startup.

<SIGH>

Suggestions or things I'm not thinking of????