Recommended slots for memory - we know they exist...why?

[Dravinian]

Why does it matter if you use the recommended slots on the motherboard for memory, if the memory is recognised and an XMP/DOCP profile can be applied to them, when they are not in those slots?

 

I ask because the people that built my PC put the memory in slot B1 and B2 where the manual recommends B2 and A2, yet the memory is recognised in the bios, and windows, the DOCP profile has applied as it should and records the appropriate speed both in the bios and in windows.

 

So why does this matter?  Why should I take the machine apart and change the RAM to the recommended slots?

[wall03]

its faster

[Dravinian]

1 minute ago, wall03 said:

its faster

Not in MHZ but in some other way?

[Matty2048]

might be based of which controller they use or be optimized so they have less interference with each other. That sort of thing

[wall03]

3 minutes ago, Dravinian said:

Not in MHZ but in some other way?

no. it is hard to explain

[MkaiL]

They'll still work but right now your sticks are configured in single channel instead of dual channel.

[Chabax]

u have 4 ram slots with 2 channels, each chanel cover a and b ram slots

[Dravinian]

2 minutes ago, MkaiL said:

They'll still work but right now your sticks are configured in single channel instead of dual channel.

So shut it down and move it over would be a good idea?

 

Also, does this mean if I bought two more sticks they would be in single channel mode each or if you fill them does that trigger something that continues to make it dual channel?

 

I ask because my intention was to add two more sticks.

[Kilrah]

The CPU has a very wide memory bus that spans "2 sticks" wide (dual channel, can be triple or quad on some platforms).

If you put the sticks in the right slots the CPU can access both sticks in one cycle, and thus read/write twice as much data per cycle.

 

As long as you add in pairs you stay in dual channel. They should all be the same type/speed or they'll all align to the slowest.

[MkaiL]

6 minutes ago, Dravinian said:

So shut it down and move it over would be a good idea?

 

Also, does this mean if I bought two more sticks they would be in single channel mode each or if you fill them does that trigger something that continues to make it dual channel?

 

I ask because my intention was to add two more sticks.

If you get another 2 sticks, both A1 - B1 and  A2 - B2 would work in dual channel mode so it doesn't technically matter but it's still better to match the same sticks with each other since they are tested to work together. If you're not adding them right away, follow the manual instructions and move your current sticks to their correct positions so they work in dual channel mode (higher bandwith).

[Guest]

5 minutes ago, Dravinian said:

So shut it down and move it over would be a good idea?

 

Also, does this mean if I bought two more sticks they would be in single channel mode each or if you fill them does that trigger something that continues to make it dual channel?

 

I ask because my intention was to add two more sticks.

You dont need to move them. Install the new sticks. It will automatically run dual channel and you're all set.

 

You will only see multitasking performance increase. The cpu doesnt care where the information is located, but having 2 channels increases bandwidth significantly.

 

Everybody has pretty much covered it. Theres not much more to it.

[Dravinian]

5 minutes ago, MkaiL said:

If you get another 2 sticks, both A1 - B1 and  A2 - B2 would work in dual channel mode so it doesn't technically matter but it's still better to match the same sticks with each other since they are tested to work together. If you're not adding them right away, follow the manual instructions and move your current sticks to their correct positions so they work in dual channel mode (higher bandwith).

Yeah cheers all, good to know, I knew they were in the wrong slots, but I always thought this meant they wouldn't be recognised properly rather than it being a dual channel thing...learn something new every day and all that.

 

Moved them over, additional RAM at some point, but not really a requirement right now, so good to know dual channel will kick in for them too.

[tech.guru]

2 hours ago, Dravinian said:

Why does it matter if you use the recommended slots on the motherboard for memory, if the memory is recognised and an XMP/DOCP profile can be applied to them, when they are not in those slots?

 

I ask because the people that built my PC put the memory in slot B1 and B2 where the manual recommends B2 and A2, yet the memory is recognised in the bios, and windows, the DOCP profile has applied as it should and records the appropriate speed both in the bios and in windows.

 

So why does this matter?  Why should I take the machine apart and change the RAM to the recommended slots?

its for it to operate in the optimal channel mode for your config,

                        dual channel, tri channel, and quad channel.

this provides more memory bandwidth

 

in order to operate in single channel mode (aka debug) they have to be installed in the correct slots in 1 DIMMS.

in order to operate in dual channel mode they have to be installed in the correct slots in 2 DIMMS.

in order to operate in tri channel mode they have to be installed in the correct slots in 3 DIMMS.

in order to operate in quad channel mode they have to be installed in the correct slots in 4 DIMMS.