Memory 101 Help

[dvancleave]

I recently purchased a Gigabyte GA-MA770-UD3 rev 1.0 motherboard and paired it with an AMD Black Edition 7750 CPU. I am a little confused on CPU/chipset limitations with respect to supported memory configurations. I have searched high and low and come across conflicting information thus far.

I am just trying to decide what memory would be best to run on this platform. Obviously speed is nice but I am more focused on stability or I would have opted for a 790 with a Phenom II Quad Core. I have read that 1066MHz is supported but only in Single Channel mode. Yet 800MHz is supported in Dual Channel mode. I am just looking to run 8 Gigabytes of RAM with 4 X 2GB sticks. Should I opt for 4 X 2GB @ 800MHz with CL5 in Dual Channel mode? Or should I opt for 4 X 2GB @ 1066MHz with CL5 or CL7 in Single Channel mode? I am not sure which would be best or if these are even my options. I would appreciate any help I could get from a H/W guru.

Thanks!!!

 

[Sylvanas]

8GB (4x2GB) on a Phenom will not run at 1066mhz (this is a limit of the memory controller on the CPU), it rolls back to 800mhz but it is still dual channel- forget single channel, nothing will force it to use that. 'Stability' will be the same as if you get 1066mhz ram or 800mhz ram, a higher frequency does not mean less stability. So, I would suggest you look into 4x2GB of 800mhz RAM, all of which is usually 5-5-5-15 and is usually cheap. The mainstream vendors are manufacturers like Corsair, Gskill, OCZ, Kingston etc- all of which will have memory worth considering but theres little real difference between them if you don't intend to overclock- so get whatever is the cheapest.

 

[n7]

If you do OC, you can get 8 GB @ speeds well over DDR2-1066 in dual channel...just an FYI.

If you don't get too excited over spending lots of time in the BIOS configuring RAM, some DDR2-800 does indeed sound just fine.

 

[dvancleave]

From what I can interpret from the information I have come across, Dual Channel mode is only supported at 800MHz with this motherboard/CPU combo. I also found some claims that only 2 DIMMs may be used at 1066MHz. I suppose that if I want to run 4 X 2GB modules in Dual Channel mode, I am confined to PC6400 (800MHz) modules. Am I correct in this? All these "limitations" with all the different platform combos can be quite confusing.