Question XMP Confusion

Cybernetic Shadow

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I have an older HP 700-515xt that's been upgraded here and there over the years. For some reason I never got around to upgrading the ram. It came with one 8gb stick of ddr3 1600 pc3-12800. According to cpu-z, the current DRAM frequency is 799mhz. That means the current stick is running at 1600mhz. I have ordered a 2x8gb kit of Corsair Vengeance LP ddr3 1600 pc3 -12800, but it says that this kit uses XMP. I do not believe my HP motherboard (Kaili2) supports XMP. Does this mean that this kit will run slower than my current stick, at 1333mhz, or will XMP allow it to go beyond 1600mhz? If it runs at 1333 that's kinda lame that a basic OEM stick can run at full speed without any overclocking, but a "name brand" kit has to be overclocked to run at advertised speeds.
 
I have an older HP 700-515xt that's been upgraded here and there over the years. For some reason I never got around to upgrading the ram. It came with one 8gb stick of ddr3 1600 pc3-12800. According to cpu-z, the current DRAM frequency is 799mhz. That means the current stick is running at 1600mhz. I have ordered a 2x8gb kit of Corsair Vengeance LP ddr3 1600 pc3 -12800, but it says that this kit uses XMP. I do not believe my HP motherboard (Kaili2) supports XMP. Does this mean that this kit will run slower than my current stick, at 1333mhz, or will XMP allow it to go beyond 1600mhz? If it runs at 1333 that's kinda lame that a basic OEM stick can run at full speed without any overclocking, but a "name brand" kit has to be overclocked to run at advertised speeds.
XMP is just set of instructions for BIOS to set it automatically to those frequencies. You should be able to set BIOS manually to whatever highest speed it supports
 

Aeacus

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XMP is essentially RAM OC, with built-in preset profile.
XMP stands for: Intel Extreme Memory Profile.

For DDR3, anything above 800/1066 Mhz is RAM OC.

I wouldn't be worried, since when your old RAM can run at 1600 Mhz, so can your new RAM, which is rated for 1600 Mhz. Though, you might need to enable the XMP profile (for 1600 Mhz) from BIOS.

Some years ago when i upgraded RAM in my Haswell build (full specs with pics in my sig), i went from 1x 8GB 1333 Mhz to 2x 8GB 1866 Mhz RAM.
 

Aeacus

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Look for RAM frequency within BIOS.

Now, all RAM sticks will run on the default JEDEC speeds (non-OC). For DDR3, it's 800 or 1066 Mhz. DDR4 has it 2133/2400/2666 Mhz. Anything above JEDEC speeds, usually, needs manual enable of RAM XMP.
 
If my current RAM is running at 1600, one would think the new one could. I hope so, as there doesn't appear to be anything in the BIOS for setting RAM speed at all.
BIOS in brand name pc can be very limited.
If you have no options in BIOS for setting XMP or changing ram settings manually, then
it's quite possible your new ram will run only at highest frequency available in JEDEC SPD profile.
Your ram might run at 1066mhz or 1333mhz only (with 1600mhz mode being unavailable).
 

Cybernetic Shadow

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I will update with the results when I recieve the new ram. That's quite annoying that I have to overclock the new ram with an unsupported profile to get it to run at the same speed as the stock ram was running in a normal JEDEC profile. That's like advertising a car with 500hp and then saying actually you have to supercharge it to get that, and your dealer might not be able to do it, so youll actually get 400hp. How big of a performance hit would I get running at 1333? I'll get a boost going to dual channel mode from single, but would that be negated by the lower clock speed? Is it worth trying to find different non-XMP ram or buying a different mobo to be able to use XMP?
 

Aeacus

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How big of a performance hit would I get running at 1333?

Difference is negligible.

For some idea, here's Linus'es video that he made about DDR4. You can check the diff between 2133 and 2666 Mhz. I'd say it's negligible;

View: https://www.youtube.com/watch?v=D_Yt4vSZKVk


or buying a different mobo to be able to use XMP?

Depends on what chipset, or better yet, what CPU you have, since that defines which MoBo you could get.

For example, my Haswell build runs i5-4590 and MoBo i have in there, is MSI Z97 Gaming 5,
specs: https://www.msi.com/Motherboard/Z97-GAMING-5/Specification

If you were to look what kind of different DDR3 RAM frequencies my MoBo supports, then you'd see it's very generous:
DDR3 MEMORY - DDR3 1066/1333/1600/1866/2000/2133/2200/2400/2600/2666/2800/3000/3100/3200/3300 HMz
I'm running 1866 Mhz DDR3 RAM in there. Though, speeds from 2133 and up, is same what DDR4 is capable of. Of course, my MoBo being Z-series means that it also offers loads of different features as well, including CPU OC, if i'd put K-series CPU in there.
 

Cybernetic Shadow

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I currently have an i7-4770. Strangely, the chipset in the HP board is Z97 but the bios offers nothing for selecting ram speeds. I also wonder if swapping the boards would cause any issues since it would be a non HP board. Wonder if i would need a clean install.
 

Aeacus

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Strangely, the chipset in the HP board is Z97 but the bios offers nothing for selecting ram speeds.

Then yes, HP has made custom BIOS for the MoBo, or the MoBo itself is proprietary all together. SI's (system integrator) are notorious in making proprietary MoBos, PSUs and PC cases, where user can't upgrade or even customize their system. Dell is worst in that regard.

I also wonder if swapping the boards would cause any issues since it would be a non HP board.

Unless CPU isn't made by HP, which it isn't (it's made by Intel), there won't be any compatibility issues. Any Intel 80- or 90-series chipset would do, while Z97 chipset is most feature rich.

What you may run into, is power connectors on MoBo. Without knowing the exact model of your MoBo, i can't look up if it has proprietary power connectors (like almost all Dell MoBos have them), or does it has standard ATX 20/24-pin and 4/8-pin power connectors.

Wonder if i would need a clean install.

Usually, new MoBo = new clean Win install.

But when you have 1 spare, free drive, you can do it without loosing any your personal data.
Idea is, that you take your old OS drive out, install Win into new empty drive, once PC boots to OS, plug in the old OS drive as data drive, and copy/paste the personal data over. Do not boot from old OS drive though. Since while Win may work, it can produce errors (BSoD).
 

Cybernetic Shadow

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Motherboard is ms-7826 (Kaili2). I have swapped cases and upgraded to an EVGA PSU and didnt run into any issues with proprietary connectors. The only original parts at this point are the mobo, cpu and ram. I recieved the new ram today and will install later. Will report my results.
 

Cybernetic Shadow

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Got the new ram installed. It did unfortunately default to 1333mhz, and I have no way of changing it, even though my mother specs say it can support 1600mhz, and I have a Z97 chip, which should support XMP. (thanks HP!) I ran some benchmarks before and after, and I noticed a 5-10fps increase going from single to dual channel. I would guess that if I were able to run the new kit at 1600, I would have seen a 10-20 fps increase. That's quite the bummer. I've essentially downgraded my ram. I would have been better off just getting a second stick of the factory ram off ebay. I may end up doing that. I feel like that's the easier option than getting a new mobo and reinstalling windows and all of that. I feel like I'm leaving performance on the table running at a gimped speed. I believe ram like this should be advertised as 1333, but 1600 available with XMP. It shouldnt be sold as 1600mhz ram, as in order to get that, you have to use a profile that not every motherboard supports. Kind of false advertising if you ask me. If an oem standard JEDEC stick is capable of running at 1600mhz, what's the point of an XMP profile? I know I've learned my lesson.
 

Aeacus

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I would have been better off just getting a second stick of the factory ram off ebay. I may end up doing that. I feel like that's the easier option

Bad idea.

Why?
Further reading (especially the "mixed memory" chapter): https://forums.tomshardware.com/faq...y-ram-and-xmp-profile-configurations.3398926/

I believe ram like this should be advertised as 1333, but 1600 available with XMP. It shouldnt be sold as 1600mhz ram, as in order to get that, you have to use a profile that not every motherboard supports. Kind of false advertising if you ask me.

The thing with PC hardware, especially compatibility is, that you have to do your due diligence.

In this case, the RAM isn't at fault, but instead the MoBo. Because MoBo lacks the proper options within BIOS, in order to utilize the RAM fully. E.g if i were to take your new Corsair RAM and put it into my Haswell build, you can be certain that it will run at 1600 Mhz.

Or on another example; e.g lets say you buy i7-4770K CPU, where the K-suffix means that you can OC your CPU (and that is your intent). But the MoBo you have is H97 chipset. So, you buy the chip, install it, and then learn from MoBo BIOS, that you can't OC your CPU. Since H97 chipset doesn't support CPU OC, only Z-series does.
Here, which is at fault? K-series CPU that can be OCd, if installed into Z-series MoBo? Or H97 chipset MoBo, which doesn't support CPU OC?

In that sense, if you would've held back your RAM purchase, made this topic beforehand, read what i said about manual XMP enable within BIOS, and learning that your MoBo BIOS doesn't support any RAM profiles (aka doing your due diligence) - would you have bought your Corsair RAM? :unsure:

If an oem standard JEDEC stick is capable of running at 1600mhz, what's the point of an XMP profile?

OEM and consumer hardware have different "application" to say so.

OEM hardware is custom made for specific build. E.g HP has tested the RAM within the factory and made sure that the RAM will run at 1600 Mhz, in that specific MoBo. Due to that, there is no need to include XMP.

Consumer RAM, in the other hand, has to have JEDEC profiles and also work at JEDEC speeds, while the XMP is secondary and often manually enabled by user. Since MoBo where that RAM is inserted, can be any that supports DDR3. Due to that, consumer RAM can not be tailored to work with only one specific MoBo, as OEM RAM is.
And in the event the XMP profile isn't stable, consumer has the option to manually insert RAM frequency and timings, or even tighten/loosen the timings, to get the advertised frequency running. Aka manual RAM OC, rather than using preset XMP profile.

For example, the DDR4 RAM (Kingston Savage) in my Skylake build (full specs with pics in my sig), is rated for 3000 Mhz. <- This is the max it can do. Due to JEDEC standard, it has to work at 2133 Mhz, and it also was at those speeds, when i 1st installed it and booted up the PC. I had to go to BIOS, and select proper XMP profile, for my RAM to run at 3000 Mhz, which it now does. My RAM also has XMP for 2666 Mhz, in an event the 3000 Mhz XMP isn't stable and/or i don't want to manually OC my RAM to 3000 Mhz (by tinkering with timings).
Now, i have Z170 chipset MoBo, which supports RAM OC. But if i were to have H110, B150 or H170 chipset MoBo, which doesn't support RAM OC, my Kingston RAM would've still worked, albeit only at 2133 Mhz speeds. Whereby me buying 3000 Mhz RAM would've been waste of money.
 
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Cybernetic Shadow

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A bit of an update for those that may be curious. I tracked down a second dimm of the exact same model number as the factory ram, and removed the corsair ram and installed the new factory spec dimm to test it. Strangely, it performed nearly as well as the 2 sticks of corsair on its own. Then, I installed both dimms of the factory spec ram, and they both ran at 1600. I ran benchmarks, maybe a VERY slight improvement over the corsair kit, if any. Just for giggles, I currently have both the corsair kit and the two factory spec dimms in, for a total of 32gb. The factory spec dimms went down to 1333 to match the corsair. I expected issues as the corsair has a cas latency of 9 while the factory spec dimms are cas 11. So far seems stable enough, running benchmarks with no errors or anything yet. Overall gaming is smoother since upgrading from a single dimm, with far less stuttering. Not that much of an FPS increase though. Seems clock speed and cas latency don't make much difference., at least speeds as close as 1333 and 1600.