DDR3 1600 C9 1.65v @ 1333 C7 1.5v Possible ?

[koolman007]

Hey guys,
I am thinking of upgrading soon from my X4 950 to i2500K. First i was thinking of getting 8GB DDR3 1600 Ram but there is no point as i will be using a 32bit OS...so i might as well use the old ram, underclock it to 1333mhz CAS7 @1.5 and save myself some money.
My current ram is 4GB kingston hyperX DDR3 1600 CAS9 1.6v...Upon reading the data sheet at kingston website i found that it will can run at 1333 @1.5v but there is no mention of how much the latency can be decreased..

Here are some of the features from data sheet...
Kingston’s KHX1600C9AD3K2/4G is a kit of two 256M x64-bit (2GB) DDR3-1600MHz CL9 SDRAM (Synchronous DRAM) memory modules, based on sixteen 128M x 8-bit DDR3 FBGA components per module. Total kit capacity is 4GB. Each module kit has been tested to run at DDR3-1600MHz at a low latency timing of 9-9-9-27 at 1.65V. The SPDs are programmed to JEDEC standard latency DDR3-1333MHz timing of 9-9-9 at 1.5V. Each 240-pin DIMM uses gold contact fingers and requires +1.5V. The JEDEC standard

JEDEC standard 1.5V ± 0.075V Power Supply
• VDDQ = 1.5V ± 0.075V
• 667MHz fCK for 1333Mb/sec/pin
• 8 independent internal bank
• Programmable CAS Latency: 5,6,7,8,9,10
• Posted CAS
• Programmable Additive Latency: 0, CL - 2, or CL - 1 clock
• Programmable CAS Write Latency(CWL) = 7(DDR3-1333)
• 8-bit pre-fetch
• Burst Length: 8 (Interleave without any limit, sequential with
starting address “000” only), 4 with tCCD = 4 which does not allow
seamless read or write [either on the fly using A12 or MRS]

please feel free to share your thoughts on best timing and speed/voltage for this ram..
Thanks

 

[koolman007]

so many views and still no answer, i wonder if its too technical for everyone out there...

 

[RetiredChief]

Download CPUID CPU-Z.
Install and open program. There are two tabs at the top; Memory, which shows what your memory is currently running at and SPD which shows what is stored in the memory Modules. Generally there are 3 settings @ 1.5 V and one (XMP) for the OCed values.

My gut feel is that if you lower the voltage you will not hit the CL7 at the lower speed, But it is possible.

For what's worth - There is not much diff between DDR1333 and and DDR 1600, infact most users willo not notice any diff. Ref an artical - 1600 is sweet spot for Sandybridge, BUT ONLY buy if it more than 10/15 bucks than 1333 then buy the 1333. (Artical in anandtech)