Mixing XMP Profile w some Manual Settings - MXI-E / 9900K ?

[rjbarker]

Hello folks...quick question, this has always been a trial an error thing and I have really not spent much time at all playing around with Memory OC'ing.

So if I set XMP 1 (or II) then F10 reboot...I know I can tweak Vram Voltage if need be....leaving AI OC in XMP mode, can I try changing DDR4 speed from say 3200 Mhz to next frequency step up, then adjust VCCIO / SA play with Timings etc .....or do I have to have AI OC mode in Manual mode ?

Im thinking you can, but I'm also thinking it maybe a little easier for me to play around as all sub timings I can leave in Auto....if I start in Manual Mode there maybe far too mnay sub timing settings......in other words start bringing up RAM Frequency / Timings (not Sub Timings) / Vram / VCCIO / SA from the XMP Profile that is set.....googled everywhere and didnt really see a specific answer to this question....

Cheers

[Nate152]

Hi rjbarker

I personally use manual mode and just set the primary timings, then raise the frequency one step at a time. The sub timings will change accordingly as you increase the frequency so there's no need to fool with those.

Most ddr4 memory can handle up to 1.50v and is the max voltage recommended by Intel. I run my trident z's at 1.55v.

If you want you could try this and see how far you get.

1) Manual Mode
2) Set the primary timings
3) Dram voltage 1.50v
4) VCCIO/SA 1.30v

5) Increase the frequency one step at a time until it becomes unstable, then back down a step.

I'd be curious to know what you started with and ended up with.

[Silent_Scone]

Hello,

If both XMP 1 and 2 profiles are stable, it's usually better to opt for XMP 1. What values are applied depends on what the memory vendor has programmed into the SPD table. This can vary from simply DRAM Voltage to VCCSA / IO and other values, too.

XMP I - Board optimised timings

XMP II - Default XMP timings


3200MHz shouldn't need more than 1.2v SA on Coffee Lake, so test frequency increases around here and increase SA if needed. Signal rails such as these can be sensitive too much voltage, so lower where possible.

[rjbarker]

Thanks guys....
I know I can go straight to Manual setting....can I set XMP Profile, then set my Frequency / Timings leaving XMP set...I know the BIOS will allow me to do this, just curious if I can go this method as well?

Hi Nate....
Thanks...so setting manual do you leave all sub timings in "auto" mode initially?

Scone....I know what XMP I&II are and what my VCCIO and SA voltages should be I presently have them set to VCIIO 1.20v and SA 1.25v.....but I also know that XMP sets other things such as sub timings and I would think perhaps some voltages other than the obvious ones (VDimm / Vram SA...VCIIO) ....I'm quite comfortable playing with those obvious voltages, primary timings and Frequency....but dont have a clue what sub timings to play with.

XMP sets ridiculously high VCCIO / SA voltage if I dont lower them manually.

[BigJohnny]

What I usually do is set it to XMP and see where it goes and record all the numbers including tertiary timings. Then go back and do it manually changing one thing at a time. Yes it tedious but gets me the best results. Not that it matters all that much as what the numbers show in memory benchmarks and what I can perceive are two very different things. In the end I cant tell the difference between just running XMP and spending several days tweaking one thing at a time to gain a little on a benchmark and nothing I can perceive. Just something I do when Im bored out of my mind with literally nothing else to do. Id rather tinker with my Harley.

[rjbarker]

BigJohnny wrote:
What I usually do is set it to XMP and see where it goes and record all the numbers including tertiary timings. Then go back and do it manually changing one thing at a time. Yes it tedious but gets me the best results. Not that it matters all that much as what the numbers show in memory benchmarks and what I can perceive are two very different things. In the end I cant tell the difference between just running XMP and spending several days tweaking one thing at a time to gain a little on a benchmark and nothing I can perceive. Just something I do when Im bored out of my mind with literally nothing else to do. Id rather tinker with my Harley.

^^^^ Yep got my answer thanks.....like someone else said on another Forum...."No problem to tweak a profile" 😉