Upgrading RAM (Asrock X99 WS). F4-2400C15Q-32GRR/K or F4-2666C15Q-32GRR

[Airbus680]

I plan to upgrade from my 4GBx4 2400 to a 32GB Kit. But I need some advice should I get the 2400 or 2666? I do some heavy workload stuff and many programs opened and gaming
Mobo is Asrock X99 WS.
The 2800 32GB Kit is on the memory support list by Asrock but the G.Skill configurator doesn't have it
While the 2666 32GB kit one is on the G.Skill configurator list but Asrock doesn't have it on the memory support list, strange...
The 2800 is not available in my local retail store so my choice is 2400 or 2666

[GSKILL TECH]

It is normal the lists are different. Each company tests with what they have. Either kit will work fine, so go with the higher frequency.

[Airbus680]

Just ordered the 2666 one. It should arrive by Wednesday.

[Airbus680]

It arrived early than expected. Installed and was automatically set to 2666. Ran Memtest 0-5, all pass. Now I am not familiar with RAM OC but there is an option in the UEFI called DRAM Frequency OC Preset. It gives me a list of presets until 3500. Is it safe/reliable to use RAM OC preset by Asrock (for people like me not familiar with RAM OC)? I want to try the 2800 and 3000 presets.

[emissary42]

The presets are just starting points for manual tweaking, so you (might/probably) have to adjust settings for absolute stability. Also keep an eye on the voltages, especially VCCSA and VDimm, since some of those presets are primarily for benchmarking, use lots of volts and are therefore not recommended for 24/7 use. Like the 4x4GB Samsung and Hynix tight and very tight profiles at 1.65V+ for example.

[Airbus680]

Thanks I might really need to learn to manual tweak for stability after choosing an OC preset. So it is safe to run Oced RAM for 24/7 use as long as the voltage is not that high?
Like this similar model but a 16GB kit : http://www.overclockers.com/g-skill-...ry-kit-review/
@3000MHz @1.35V 16-16-16-36
but then I saw an exact model and kit:
http://www.overclockers.com/forums/s...2666C15Q-32GRR
"3000 or anything above wasn't possible. Memory was simply not working and board was showing 55 error code. The same at much more relaxed timings and voltage up to 1.45V."

[GSKILL TECH]

There's no AUTO OC, or OC presets that will work better than a custom / manual tune. The proper profile is XMP, which is what Intel and manufacturers recommend. While automatic overclocking sounds like a great idea, it is a random attempt by the system and almost every time it is nothing near the RAM's actual capability.

It's not difficult to learn and OC the right way especially with so many guides and users online with similar hardware that can help.