Right now, I could choose between the following setups that have proved stable:
a) 64GB (8x8) running at 1,600Mhz and 8-8-8-24 timings, and 1.5 volts
b) 32GB (8x4) running at 1,866Mhz and 9-10-9-27 timings, and 1.5 volts
c) 32GB (8x4) running at 2,133Mhz and 10-11-10-30 timings and 1.57 volts
Questions for you:
1) Which of the 3 scenarios above would you choose and why?
2) Any suggestions for trying to reach 1,866Mhz with all 8 sticks installed?
3) Will any of the setups unduly hinder my future CPU overclock goals?
4) How bad is it to run 1.5 volt memory at 1.57 if you keep it up 24/7?
5) Max DRAM voltage I should consider safe for a 24/7 box?
1. C unless I confirmed that the applications I was using would actually use enough RAM to have the extra 32GB be used. As far as I've seen, the only apps that would use that much are server processes, rendering, and custom-configured/made video encoding/decoding. To be honest, the inclusion of a very large RAID 0 SSD array negates most of the need for excess RAM. 64GB will be slower (and I'm not just talking about 2133 vs 1600; 32GB @ 1600 would be faster than 64GB @ 1600). It is also possible that having 8 dimms will not allow the motherboard to run quad-channel RAM, which would cause noticeable performance decreases across the board.
2. Play around with the DIMM and IMC voltages and settings. There are some very good guides from the GSkill techs that can also be used as reference when using other vendors' RAM. Also remember that increasing the timings will usually allow higher clocks (to a point).
3. Yes. Which ones and by how much depend on too many factors though. You'll just have to try them all.
4. As mentioned before, RAM (especially flagship RAM) has a pretty wide margin available for play. What's more, if your RAM is water cooled, you have even less to worry about.
5. I've read some people run at 1.7, but I personally wouldn't feel comfortable over 1.6 or 1.65. Upping DRAM voltage doesn't seem to help as much in OC as it did in the past. Also remember that playing with your IMC settings will affect RAM speeds and required voltages for stability as well.Edited by Electrocutor - 11/17/12 at 8:22am