[SOLVED] Should I bother moving my RAM to the "recommended slots"?

Adam1998

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Some context here, my system has 16gb of ram which works absolutely fine and has done for over 3 years. But I realized recently that my ram was running slower than it should which I can sort in the bios simply. But reading up I noted that my ram is in the a1-b1 orientation where as Asus recommends a2-b2. Even though it works fine, should I change it? I actually swapped it when I first built it because bit was only detecting 8gb and this set-up worked.

My mobo is the Asus Prime Z270-a for context
 
Solution
Ok, well in my experience those should probably be compatible regardless of what the exact model is.

The first thing I'd do is make sure you have the most recent motherboard BIOS version installed. That is typically one of the biggest reasons why some memory may not be fully compatible. Then, after updating, check to see that they work in the correct slots. You might also need to do a hard reset of the BIOS after changing slots.

BIOS Hard Reset procedure

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for five minutes. In some cases it may be necessary to remove the graphics card to access the CMOS battery.

During...
Yes, you SHOULD change it. There are specific architectural reasons, related to signal quality, for the primary slots being designated AS the primary slots. Often, on many platforms or motherboards, populating the wrong DIMM slots will result in a lack of full capacity being recognized, failure to work when XMP or full manual speed configuration is set, failure to run in dual channel or simply more poorly configured secondary and tertiary timing configuration by the motherboard, which generally determines what the secondary and tertiary timings are set at. These can have a a pretty moderate effect on actual performance.

If for any reason you can't successfully use a memory kit that is known to be good, in the correct slots, then there is a reason for it. Either the memory isn't fully seated or is seated incorrectly, or the CPU cooler is too tight on one side or unevenly tightened, or there is one or more bent pins on the CPU that affect memory performance on that slot or slots, or a bad board, or bad memory. Something. Memory doesn't not work in the second and fourth slots for no reason. There is always a reason why it doesn't work correctly in those slots and in some cases that reason may be that the memory simply isn't fully compatible with that motherboard.

The fact that yours do work in the first and third slots would tend to rule that out, but you never know, because if they are operating at the base JEDEC SPD configuration, then it is likely that you can't take the fact that they are working in those slots as proof that they ARE in fact fully compatible.

What is the exact model of your memory kit?
 

Adam1998

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Yes, you SHOULD change it. There are specific architectural reasons, related to signal quality, for the primary slots being designated AS the primary slots. Often, on many platforms or motherboards, populating the wrong DIMM slots will result in a lack of full capacity being recognized, failure to work when XMP or full manual speed configuration is set, failure to run in dual channel or simply more poorly configured secondary and tertiary timing configuration by the motherboard, which generally determines what the secondary and tertiary timings are set at. These can have a a pretty moderate effect on actual performance.

Okay that's no issue, good thing ram is nice and simple to swap over. But in the instance that it only recognises 8gb again, what would you recommend I do?
 

Adam1998

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^^^Look again.

Oh I didn't realize it was more than 1 paragraph. In terms of the memory itself, I can't give an exact right now but I know it's Corsair Vengeance 3000mhz, 2x 8gb.
I did speak to a friend recently that pointed out he had the same issue and it fixed after he swapped the ram about until it worked where it needed to, not sure why
 
Ok, well in my experience those should probably be compatible regardless of what the exact model is.

The first thing I'd do is make sure you have the most recent motherboard BIOS version installed. That is typically one of the biggest reasons why some memory may not be fully compatible. Then, after updating, check to see that they work in the correct slots. You might also need to do a hard reset of the BIOS after changing slots.

BIOS Hard Reset procedure

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for five minutes. In some cases it may be necessary to remove the graphics card to access the CMOS battery.

During that five minutes, press the power button on the case, continuously, for 30 seconds. After the five minutes is up, reinstall the CMOS battery making sure to insert it with the correct side up just as it came out.

If you had to remove the graphics card you can now reinstall it, but remember to reconnect your power cables if there were any attached to it as well as your display cable.

Now, plug the power supply cable back in, switch the PSU back on and power up the system. It should display the POST screen and the options to enter CMOS/BIOS setup. Enter the bios setup program and reconfigure the boot settings for either the Windows boot manager or for legacy systems, the drive your OS is installed on if necessary.

Save settings and exit. If the system will POST and boot then you can move forward from there including going back into the bios and configuring any other custom settings you may need to configure such as Memory XMP, A-XMP or D.O.C.P profile settings, custom fan profile settings or other specific settings you may have previously had configured that were wiped out by resetting the CMOS.

In some cases it may be necessary when you go into the BIOS after a reset, to load the Optimal default or Default values and then save settings, to actually get the hardware tables to reset in the boot manager.

It is probably also worth mentioning that for anything that might require an attempt to DO a hard reset in the first place, IF the problem is related to a lack of video signal, it is a GOOD IDEA to try a different type of display as many systems will not work properly for some reason with displayport configurations. It is worth trying HDMI if you are having no display or lack of visual ability to enter the BIOS, or no signal messages.

Trying a different monitor as well, if possible, is also a good idea if there is a lack of display. It happens.
 
Solution

Adam1998

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Dec 26, 2015
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Ok, well in my experience those should probably be compatible regardless of what the exact model is.

The first thing I'd do is make sure you have the most recent motherboard BIOS version installed. That is typically one of the biggest reasons why some memory may not be fully compatible. Then, after updating, check to see that they work in the correct slots. You might also need to do a hard reset of the BIOS after changing slots.

BIOS Hard Reset procedure

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for five minutes. In some cases it may be necessary to remove the graphics card to access the CMOS battery.

During that five minutes, press the power button on the case, continuously, for 30 seconds. After the five minutes is up, reinstall the CMOS battery making sure to insert it with the correct side up just as it came out.

If you had to remove the graphics card you can now reinstall it, but remember to reconnect your power cables if there were any attached to it as well as your display cable.

Now, plug the power supply cable back in, switch the PSU back on and power up the system. It should display the POST screen and the options to enter CMOS/BIOS setup. Enter the bios setup program and reconfigure the boot settings for either the Windows boot manager or for legacy systems, the drive your OS is installed on if necessary.

Save settings and exit. If the system will POST and boot then you can move forward from there including going back into the bios and configuring any other custom settings you may need to configure such as Memory XMP, A-XMP or D.O.C.P profile settings, custom fan profile settings or other specific settings you may have previously had configured that were wiped out by resetting the CMOS.

In some cases it may be necessary when you go into the BIOS after a reset, to load the Optimal default or Default values and then save settings, to actually get the hardware tables to reset in the boot manager.

It is probably also worth mentioning that for anything that might require an attempt to DO a hard reset in the first place, IF the problem is related to a lack of video signal, it is a GOOD IDEA to try a different type of display as many systems will not work properly for some reason with displayport configurations. It is worth trying HDMI if you are having no display or lack of visual ability to enter the BIOS, or no signal messages.

Trying a different monitor as well, if possible, is also a good idea if there is a lack of display. It happens.

I'll give it a whirl tomorrow and let you know the results back here, hopefully it's a bios update as there is one version I'm behind on
 
Yes, the latest version specifically outlines:

Improved system stability.
Improve system performance.
Updated Intel CPU microcode.
Improved DRAM compatibility.

So there's a good chance that it will be helpful. Keep in mind, AFTER you update the BIOS, it is a GOOD idea to either do a full hard reset and switch the DIMM slots while the system is powered off during the reset, or at the very least, after doing the update, to go into the BIOS and select the option to load the Setup default or Optimal default settings. You will of course then have to reconfigure any custom settings like fan profiles, overclock settings, enabling XMP, etc. that you had configured prior to the reset and that you will want to be sure you are in the advanced mode when you do that. EZ modes don't typically give you anything beyond the most basic options.
 

Adam1998

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Dec 26, 2015
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Yes, the latest version specifically outlines:

Improved system stability.
Improve system performance.
Updated Intel CPU microcode.
Improved DRAM compatibility.

So there's a good chance that it will be helpful. Keep in mind, AFTER you update the BIOS, it is a GOOD idea to either do a full hard reset and switch the DIMM slots while the system is powered off during the reset, or at the very least, after doing the update, to go into the BIOS and select the option to load the Setup default or Optimal default settings. You will of course then have to reconfigure any custom settings like fan profiles, overclock settings, enabling XMP, etc. that you had configured prior to the reset and that you will want to be sure you are in the advanced mode when you do that. EZ modes don't typically give you anything beyond the most basic options.

So strangely a straight swap worked, I'll still do a bios update to remove any possibility of issues but it's possible I just never had it plugged in right when I first built it given it was my first ever pc build. Thanks for the help regardless
 
Yeah, absolutely. For the future, just remember, regardless of what the manufacturer is calling the slots, for two DIMMs on any dual channel motherboard (So far at least, and it's always a good idea to look at the manual just to verify in case they change something in the future), it is ALWAYS the second and fourth slots.

Sometimes, also, you can have everything installed correctly and it won't work, and then removing and reinserting it (Graphics card, memory, whatever) just "works" suddenly for whatever reason.

Glad you got it working properly.