I have been using 4GB of 800MHz DDR2 for a few years now and decided it was time to upgrade, so I bought 2x 4GB 1333MHz sticks (as mentioned earlier, they are Corsair XMS3). I am using an ASUS P5KC motherboard which has 4 DDR2 slots and 2 DDR3 slots, but it seems to just not register the DDR3 ones at all. As I write this I have both one stick of DDR2 and one of DDR3 in my motherboard, and obviously my computer is fine. Is it most likely the DDR3 sticks just aren't working? I've tried unplugging my hard drives and DVD drive and having only one, the other and both of the DDR3 sticks in at any one time, but the computer has never booted. I'm using a C2D E8200, a GeForce 9600GT, Samsung 1TB and Maxtor 500GB hard drives.
If my memory serves me correctly, you can only use DDR2 or DDR3, you can't use both at the same time. I'll do some more research now. Edit: Yep. Page 38 of the manual, "You can only install either DDR2 module(s) or DDR3 module(s) on the motherboard; otherwise, the system will not boot up."
Yeah you're right, I was just plugging them both in because I was curious as to what would happen. I have established now that one of the sticks doesn't work, however another issue has presented itself. Each stick individually should be more powerful than my old two sticks (4GB 1333MHz vs. 4GB 800MHz), yet when I had the one working 1333 stick in, the "Windows Experience Index" scored a 6.4 on the memory. With my old DDR2 in, it scores a 6.7. Can anyone explain this? I am in the process of returning the memory, hopefully the replacement will be working!
I wouldn't worry about the WEI number, the 1066MHz DDR2 in my PC scores 7.7 as a reference. As long as the PC at least feels as fast, I wouldn't worry about it. It's probably the fact that a single stick will only run in single channel mode rather than the 2 sticks of DDR2 in dual channel mode causing the lower number.
That's what I have done, just one of the DDR3 sticks doesn't work. I'm going to return it as soon as possible so hopefully it's all up and running within a week.
