G.Skill F3-2133C11D-16GZL

[Flux030]

Hallo!

I recently bought this ram (G.Skill F3-2133C11D-16GZL). I own a sandybridge i7-2600k and a Gigabyte P67A-UD4.

Sadly the ram only works with 1333 Mhz and wont work with the XMP-presets at 1800 or 2133Mhz. I know the "normal" frequency for sandybrdge is 1333Mhz but it should work up to 2133. Im no pro at overclocking and the only thing i tried so far was upping the VCCIO in steps up to 1.20 (because i read that in overclock.net guide) but nothing helped, system never boots. I also tried entering the frequencyies/latencies by hand (no XMP-preset) but also didnt work.
I tried setting the frequency to 1600Mhz and leaving everything on auto. With this setup the system boots but produces a bluescreen when running prime.

Anything else i can try to make the ram run at at least 1600? Any help appreciated.
thanks in advance.

[emissary42]

You probably only need to raise VCCIO a little bit, but the VCCSA needs a bump as well.

Also you probably want to check with Aida64, Thaiphoon Burner or some other utility what tRFC the kit needs for DDR3-2133 and if the value is over the maximum value your board can set. That is a common limitation of most P67 models when it comes to 8GB modules at higher frequencies. You can try to set the max value for it and see if you get DDR3-1600 working and then move your way up, but at some point stability might be impacted or the board just fails to POST at all.

[oobymach]

To get my 2133mhz ram to run without freezing the computer I had to adjust timings as follows, keep in mind my timings are for a quad channel kit running in dual channel mode.

10--12---12---34---7----41---16---8----8-----10----33---auto--350ns-350ns
tCL tRCD tRP tRAS tRTP tRC tWR tRRD tWTR tCWL tFAW tREF tRFC0 tRFC1

things you need to know setting up timings

tRAS = tCL + tRCD + tRP

tRC = tRAS + tRTP

tWR = tRTP + tCL (max 16)

tFAW = tRRD + tWTR + tCWL + tRTP

Follow those rules and your ram will run at the recommended voltage and timings whereas it will not if one those numbers are out by even one in most cases. My ram isn't 100% stable, prime 95 fails one worker after about 15 minutes of stress but it's fine to play games with now where before with default timings I had game crashes every 5 mins and less than 4 minutes stability in prime 95. The 2 numbers that matter most are tFAW and tRAS, if they're not correct the system will be unstable, even though other guides say +/- 1 for tRAS don't set it -1 or it will result in instability.