Understanding and using XMP

[Praz]

XMP is often viewed as plug n' play when overclocking memory. As is the case when overclocking other system components memory stability may not be achievable by simply enabling XMP.


XMP will have been fully qualified by the memory manufacturer. This testing is done on a sample of boards the manufacturer has in there possession and/or by machine testing. The motherboard manufacturer likewise qualify specific memory sets for motherboards using provided memory sets, board samples and design/test data. The following are important considerations to keep in mind when relying on XMP as an overclocking option:


Using XMP is not running the system at default stock settings. Any memory setting that differs from JEDEC or processor manufacturer specifications is an overclock.


XMP is valid only for the set of memory that is purchased. Mixing modules or combining kits results in the XMP profile being no longer valid.


Regardless of what may be assumed from marketing XMP does not guarantee automatic overclocking. The tighter the timings or higher the frequency compared to stock specifications the more likely chance there is that the user will need to manually make some adjustments for stability.


To increase the probability of XMP being successful and when overclocking memory in general purchase memory kits one or two bins lower than the maximum the motherboard is qualified for.


The biggest variable of XMP being successful will be the capabilities of the processor's IMC. As with CPU speed memory overclocking success will vary from one CPU sample to the next.


When enabling XMP it is normal and should be expected that the board will alter other settings as well as voltages. These changes are set up to accommodate the processors at the lower end of the lot sampled. Especially with voltages it is the responsibility of the user to change these values to amounts that suit the particular CPU and configuration being used. Below are examples of some of the voltages that were altered by enabling XMP. As can be seen this CPU requires considerably less IO, SA and Standby voltages for stability than initially set.




XMP enabled









XMP enabled with IO, SA and Standby voltages adjusted to match the needed values for the CPU

[SherardG]

Thanks for this comprehensive guide! When you lowered the VCCIO, SA, and CPU Standby, how did you arrive at these values?

Is your 8700K Delidded? That temperature is low!

[Dovakhan]

No hard feelings towards the OP (it's not his fault anyway), but why do I get the feeling that this thread was made sticky as a response to my complains? If I'm right, that'd be SO infantile...(yet again).

But OK, I'll bite. Loaded BIOS defaults, and the only option I modified is SVID at Best Behaviour (so XMP is disabled and RAM at default 2133, also verified that in HWiNFO64). And the voltages are still EXACTLY THE SAME, and I'm still having EXACTLY THE SAME ISSUES as when I have it enabled.

Next excuse, please?

[Praz]

SherardG wrote:
Thanks for this comprehensive guide! When you lowered the VCCIO, SA, and CPU Standby, how did you arrive at these values?

Is your 8700K Delidded? That temperature is low!

Hello

Change the voltages or settings in small steps and retest for stability. In this instance I know what this CPU is capable of so I set 1V for all 3 settings. With further tuning the voltages can most likely be reduced further in this instance. Yes, the CPU is delidded.

Dovakhan wrote:
No hard feelings towards the OP (it's not his fault anyway), but why do I get the feeling that this thread was made sticky as a response to my complains? If I'm right, that'd be SO infantile...(yet again).

But OK, I'll bite. Loaded BIOS defaults, and the only option I modified is SVID at Best Behaviour (so XMP is disabled and RAM at default 2133, also verified that in HWiNFO64). And the voltages are still EXACTLY THE SAME, and I'm still having EXACTLY THE SAME ISSUES as when I have it enabled.

Next excuse, please?

Hello

See my post in your latest thread.

https://rog.asus.com/forum/showthread.php?98027-Did-some-tests-so-you-don-t-have-to-Basic-voltage-ta...

[no1yak]

The thing is that all your overclocking, XMP is marketing hype. If you have a CPU that's half decent ,then yes you can possibly over clock your CPU and memory. It's called silicon lottery. We have had a few boards lately, starting with the Z270 and, now the Z370. Ever since Intel put the IMC in their chips there has been problems with users trying to get their memory to run at XMP speeds. Asus claiming that some of their boards can run memory at 4000, or 3800 is fine if you have a good CPU. I also think that Asus will get around to up dating their bios's to make the over voltage problems that a lot of users are having.

At the end of the day - you pays your money and you take a chance.

[no1yak]

The thing is that all your overclocking, XMP is marketing hype. If you have a CPU that's half decent ,then yes you can possibly over clock your CPU and memory. It's called silicon lottery. We have had a few boards lately, starting with the Z270 and, now the Z370. Ever since Intel put the IMC in their chips there has been problems with users trying to get their memory to run at XMP speeds. Asus claiming that some of their boards can run memory at 4000, or 3800 is fine if you have a good CPU. I also think that Asus will get around to up dating their bios's to make the over voltage problems that a lot of users are having.

At the end of the day - you pays your money and you take a chance.

[Silent_Scone]

Great post, Praz. Covers ground that most users often overlook.

Dovakhan wrote:
No hard feelings towards the OP (it's not his fault anyway), but why do I get the feeling that this thread was made sticky as a response to my complains? If I'm right, that'd be SO infantile...(yet again).

But OK, I'll bite. Loaded BIOS defaults, and the only option I modified is SVID at Best Behaviour (so XMP is disabled and RAM at default 2133, also verified that in HWiNFO64). And the voltages are still EXACTLY THE SAME, and I'm still having EXACTLY THE SAME ISSUES as when I have it enabled.

Next excuse, please?

I think you're flattering yourself too much. This is basic ground when it comes to memory overclocking and buying binned kits, and something that comes up time and time again. Memory is a complex subject that can't really be covered completely as it's outside the scope of what the end user will understand. What this post from Praz does, is tell you exactly what the profile does and the implications of it. Whether one chooses to accept that or not is down to that individual.

[Carbonicdk]

Probably also doesn't help that Z370 got released early and thus tends to have issues with XMP and memory overclocking in general. Bios probably needs a lot of work and there's sadly not been as many updates as I expected there would.

[Dovakhan]

Carbonicdk wrote:
Probably also doesn't help that Z370 got released early and thus tends to have issues with XMP and memory overclocking in general. Bios probably needs a lot of work and there's sadly not been as many updates as I expected there would.

I'm emailing ASUS support about those issues, seeing how the mods here are more interested on deleting messages rather than reporting them to the techs and giving status updates. It'd be nice if everybody with those voltage issues here did the same.

Now, if only they could reply more than once a week, maybe we could get all the issues solved.

[Praz]

Dovakhan wrote:
I'm emailing ASUS support about those issues, seeing how the mods here are more interested on deleting messages rather than reporting them to the techs and giving status updates. It'd be nice if everybody with those voltage issues here did the same.

Now, if only they could reply more than once a week, maybe we could get all the issues solved.

Hello

This thread is for XMP specific topics only. It is not a dumping ground general whining and moaning. All future off topic posts will be removed without notification.