Existing DDr3 corsair XMS3 1066 mhz can i add 3x2 gigs 1600mhzwill it default to

[billysumner]

Hi
I have a present 3x2 gigs of Corsair XMS 3 ram running at 1066 mhz. If I add an additional 3x2 gigs of 1600mhz will this autpomatically default to 1066mhz?

Motherboard Gigabyte X58A - udr3 rev1

Regards
Bill

 

[jaquith]

Welcome to Tom's Forums!

I have the GA-X58A-UD3R (rev 2) and it 'should' if the BIOS is set to Load Optimized.

However, I would strongly encourage you not to mix-match your RAM; Corsair's are very good and if you had something like Patriot or OCZ then my answer would be a resounding DON'T do it.

The 'problem' is that you will more than likely need to Manually set the Speed, CAS, and perhaps the DRAM Voltage at the WORST of each set.

Examples:
TR3X6G1600C8D - 1600 8-8-8-24-2T @ 1.65V
CMX6GX3M3A1333C9 {XMS} 1333 9-9-9-24-2T @ 1.50V

1600 8-8-8-24-2T @ 1.65V <- @ 1333 9-9-9-24-2T runs slower
1333 9-9-9-24-2T @ 1.50V <- @ 1.60V runs hot
===================
1333 9-9-9-24-2T @ 1.60V

Also, keep in mind in the example {BOTH} sets have different {lower} CAS timings running under-clocked at 1066 MHz. Further, IF you choose XMP in the BIOS then I guarantee BSOD, Post Failure, and/or the PC being Unstable.

Therefore, again I recommend purchasing IDENTICAL {XMP} Corsairs, and do NOT even mix-match those {sets} in the DIMM slots - which can ALSO cause issues.

Install in {sets} set1 -> DDR3_1, DDR3_3, DDR3_5 ; set2 -> DDR3_2, DDR3_4, DDR3_6

I hope this illustrates the Pros & Cons and answers your questions. Use Best Practices.

Good Luck!