I have an XPS 710, with a 1mghz power supply, and a Q6600 quad prodessor, and have just installed Corsair 2x2 (4 GB) of DDR2 800 Ram, but PC Wizard tells me the Ram is running at 1.8v --and the Dell Upgrade advisor recommended these 1.9v modules because I have the 1 mghz voltage needed to run this RAm. What do I do? It's reading as DDR2 6400. Cl 5
With a Dell M/B more than likely manually setting memory voltage is not a BIOS option for you, what you could do however is, with the new memory in the computer, pull the power to the computer, clear the CMOS setting by either a jumper or actually pulling the M/B CMOS battery for about 90sec.
Replace everything, Bootup, enter the setup, and reset the Date and Time in the CMOS setup, save, and exit, that will give the system a fresh hardware reset and may just recognize the proper voltage setting.