Used Crucial's scan tool and they recommended two 4GB DDR3-1600. Bought them.
Originally had 2 Kingston GB DDR3-1333 in two slots, and 2 Kingston 1GB DDR-1333 in the other. Replaced the 1GB pair, System worked for four months, and I started getting blue screen crashes every day. Went back to the 1GB pair, and sent the Crucial parts back for replacement, That process took five weeks due to mail issues, but no blue screens with old configuration.
New sticks arrived today. The PC will not boot if I install only Crucial RAM in either DIMM0/1 or DIMM2/3. Four beeps. Boots with Crucial parts in DIMM2/3 and Kingston parts in DIMM0/1. Running memtest at the moment. .
Question is ...Does the XPS7100 auto select different RAM timing for each bank, or did I have to select that in BIOS setting?
By the way, system boots with Kingston 2GB in DIMM0 and Crucial 4GB in DIMM1. I thought they had to be matched pairs?
Oh yeah. I checked the BIOS. Nothing to do there. I did replace the CMOS battery though, First time ever since 2011.
Memtest passed one cycle. Just as I was ready to power off, it picked up an inversion error.
So running memtest again with all six cores of my AMD enabled.
Have you tested all the memory slots one at a time with only one memory chip at a time? (one chip in slot 1, reboot then same chip in slot 2 then 3 then 4 etc. Then try a diff chip same way.)That way you can see if it is a bad chip or a bad memory slot or both. I'm guessing you might have a bad slot on the motherboard.
Memory slots are 1 & 2 (matched pair of ram for the 7100) and 3 & 4. Put the same ram chips in 1 & 2 and the other set in 3 & 4. You don't have to match memory but matched sets run better since different ram will run all the memory at the slower speed. That is why you should have 2 sets of matching ram--all 4 the same size, speed and brand. Here's the service manual: http://downloads.dell.com/manuals/all-products/esuprt_desktop/esuprt_studio_xps_desktop/studio-xps-7...
Sata ports are 0 - 4 but memory slots are 1 - 4.