Quad ram

[Wavguy]

Hello, can someone educate me on what the difference of running dual or quad ram is?

[fordy_rounds]

That depends a lot on your motherboard and CPU. If they both support quad-channel, then running 4 sticks will get you better speed, as you can access all 4 simultaneously. However, some motherboards and CPUs only support dual channel, so using four sticks is no better than two (except that you might be able to get higher capacities) since you'll have two sticks (usually 1 and 3) on one channel and the other two (2 and 4) on the second.

[Wavguy]

I got the i9 9900k and gigabyte Aorus Master I read that the i9 9900k doesn’t support quad.

[mariushm]

First you have to understand what dual and quad means.

 

having 4 sticks on the motherboard doesn't mean quad channel.

 

Depending on how many channels the memory controller inside the processor has, you can have dual channel (2 or 4 slots - amd am3, am4 , intel 115x boards ) , triple channel (3 or 6 memory slots - some intel stuff) or quad channel (4 or 8 slots - threadripper for example )

 

This dual channel, triple channel, quad channel means the processor can read and write data to 2, 3, or 4 sticks at the same time, in parallel, this way reducing the amount of time it takes to complete reading or writing some amount of data.

For example, if the processor writes 1 GB of data in 10 seconds to the RAM, in dual channel mode the processor writes 512 MB in the first stick at the same time it writes the other 512 MB in the second stick, so it will actually take half the time (5 seconds) to complete the write process...

 

On a dual channel platform (for example socket AM4 motherboard), you can have 2 slots or 4 slots.. no matter what, the system will be dual channel, because processors only have 2 channels.

If you install 4 sticks, you'll just have 2 sticks per channel, but you don't get higher speed, better performance compared to having only 2 sticks.

Well, it's super technical and too difficult to explain, but in SOME cases there may be a very tiny performance increase when using 4 sticks of memory but typically it's not worth going out of your way to buy 4 sticks instead of just 2 bigger capacity sticks.

 

 

[Wavguy]

4 minutes ago, mariushm said:

First you have to understand what dual and quad means.

 

having 4 sticks on the motherboard doesn't mean quad channel.

 

Depending on how many channels the memory controller inside the processor has, you can have dual channel (2 or 4 slots - amd am3, am4 , intel 115x boards ) , triple channel (3 or 6 memory slots - some intel stuff) or quad channel (4 or 8 slots - threadripper for example )

 

This dual channel, triple channel, quad channel means the processor can read and write data to 2, 3, or 4 sticks at the same time, in parallel, this way reducing the amount of time it takes to complete reading or writing some amount of data.

For example, if the processor writes 1 GB of data in 10 seconds to the RAM, in dual channel mode the processor writes 512 MB in the first stick at the same time it writes the other 512 MB in the second stick, so it will actually take half the time (5 seconds) to complete the write process...

 

On a dual channel platform (for example socket AM4 motherboard), you can have 2 slots or 4 slots.. no matter what, the system will be dual channel, because processors only have 2 channels.

If you install 4 sticks, you'll just have 2 sticks per channel, but you don't get higher speed, better performance compared to having only 2 sticks.

Well, it's super technical and too difficult to explain, but in SOME cases there may be a very tiny performance increase when using 4 sticks of memory but typically it's not worth going out of your way to buy 4 sticks instead of just 2 bigger capacity sticks.

 

 

So what about the motherboard I am running isn’t a T-topology board which requires 4 ram in all slots or can I just use 2?

[mariushm]

42 minutes ago, Wavguy said:

So what about the motherboard I am running isn’t a T-topology board which requires 4 ram in all slots or can I just use 2?

No motherboard REQUIRES a specific number of sticks.

All boards can run with 1, 2, 3 or 4 sticks ... though some boards will complain about 3 sticks.

 

T topology refers just to the way the wires go from the cpu socket to the memory slots and how the connection is made between each pair of slots that will work in parallel to complete operations faster.

In T topology, for each data pin in the memory slots (around 100+ of them) there's a wire going between the two slots and from there there's a T or more like a Y and there's two tiny wires (a few mm long) going to identical pins on each slot. The usual way is to go with the wire to the pin on the first slot and then continue to 2nd slot with a longer wire.

It's just a different way of making the connection between cpu socket and memory slots. 

This makes the layout more difficult as there's more actual wires on the circuit board, but the advantage is that no matter what data the processor requests, the amount of time to get the data is the same no matter in which slot the data is physically located. The length of wire from cpu pins to memory slot is the same to the mm no matter the slot

In the more common design, the 2nd slot is at the end of the wire, with a few mm / thousands of an inch further away from the cpu, which in theory means a few picoseconds of delay.

so because there's no such ridiculously small delay when dealing with the 2nd pair of sticks, you could argue t topology is better if you're gonna use 4 sticks, and the memory controller will also have a easier time working with 4 sticks so there's potential to achieve higher frequencies with 4 sticks installed.

 

So you can use 2 ... your board with t topology layout will be just as good as the regular topology board and offer no actual benefits unless you're trying to overclock your ram sticks to the extreme.