Question What is Bus Speed in CPU specification??????

Apr 6, 2021
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Bus are the path through which information travels from one place to another but
If you go on intel product page spec of
  1. processor 1165g7 then there under CPU specification Bus Speed is 4GT/s and for that max memory support is DDR4-3200, LPDDR4x-4267.
  2. If we see specs of 1160g7 then its Bus Speed is 2GT/s and for that max memory support is LPDDR4x-4267.
3. and in case of 10750h then Bus Speed is 8GT/s and for that max memory support is DDR4-2933.

What is the purpose of processor bus speed ?? If we see second processor it has bus speed of only 2GT/s but it is supporting DDR4-4267 then what is the purpose of higher bus speed (as in 1st processor bus is 4gt/s but max memory is same)??????
 

Mr.Spock

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Dec 8, 2019
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you're confusing multiple items - cpu bus vs memory bus vs DDR4 RAM data rate.
the 2GT/s vs 4GT/s may be dependent on the chipset e.g. PCI-E 3.0 vs 4.0 - DDR4-4267 is a multiple of Data Rate which is 2133MHz.
 
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Apr 6, 2021
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your confusing multiple items - cpu bus vs memory bus vs DDR4 RAM data rate.
the 2GT/s vs 4GT/s may be dependent on the chipset e.g. PCI-E 3.0 vs 4.0 - DDR4-4267 is a multiple of Data Rate which is 2133MHz.
I am asking about cpu bus speed. What is the purpose of 2gt/s and 4gt/s?
 
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What is the purpose of processor bus speed ?? If we see second processor it has bus speed of only 2GT/s but it is supporting DDR4-4267 then what is the purpose of higher bus speed (as in 1st processor bus is 4gt/s but max memory is same)??????
The little question mark explains:

"A bus is a subsystem that transfers data between computer components or between computers. Types include front-side bus (FSB), which carries data between the CPU and memory controller hub; direct media interface (DMI), which is a point-to-point interconnection between an Intel integrated memory controller and an Intel I/O controller hub on the computer’s motherboard; and Quick Path Interconnect (QPI), which is a point-to-point interconnect between the CPU and the integrated memory controller. "

I can imagine the bus they could be specifically referring to is the QPI...you can read more about that here:
https://en.wikipedia.org/wiki/Intel_QuickPath_Interconnect
 
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Apr 6, 2021
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The little question mark explains:

"A bus is a subsystem that transfers data between computer components or between computers. Types include front-side bus (FSB), which carries data between the CPU and memory controller hub; direct media interface (DMI), which is a point-to-point interconnection between an Intel integrated memory controller and an Intel I/O controller hub on the computer’s motherboard; and Quick Path Interconnect (QPI), which is a point-to-point interconnect between the CPU and the integrated memory controller. "

I suspect the bus they refer to is the QPI...you can read more about that here:
https://en.wikipedia.org/wiki/Intel_QuickPath_Interconnect
what i wanted to know is how higher processor bus speed is going to affect its performance? processor have 2gt/s, 4gt/s , 8gt/s speed. Are those speed only limited upto inside processor (i.e interchanging data from l1 to l3 etc.)???
 

dorsai

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what i wanted to know is how higher processor bus speed is going to affect its performance? processor have 2gt/s, 4gt/s , 8gt/s speed. Are those speed only limited upto inside processor (i.e interchanging data from l1 to l3 etc.)???
You're confusing bus speed with bus width. Look at the cpu details a little closer...the major differences between the two cpus comes down to three items. The first difference is clock speed, the second is power consumption, the third is memory size supported. Clock speed and power consumption are not solely dependent on bus speed since clock multipliers can manipulate both. The one item that appears to be fixed is memory size supported. One processor supports 32 gig and the other supports 64 gig....that's what 2gt/s vs 4gt/s gets you.
 
Reactions: Nikhilniks
Apr 6, 2021
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You're confusing bus speed with bus width. Look at the cpu details a little closer...the major differences between the two cpus comes down to three items. The first difference is clock speed, the second is power consumption, the third is memory size supported. Clock speed and power consumption are not solely dependent on bus speed since clock multipliers can manipulate both. The one item that appears to be fixed is memory size supported. One processor supports 32 gig and the other supports 64 gig....that's what 2gt/s vs 4gt/s gets you.
Ohh ,yes! Thanks.
So more bus speed signifies means more memory???
Is there no difference in terms of performance other than max memory size????
 

dorsai

Distinguished
Ohh ,yes! Thanks.
So more bus speed signifies means more memory???
Is there no difference in terms of performance other than max memory size????
It would be better to think of it as more bus "width" means more memory supported...that's what the 2gt/s vs 4gt/s really indicates although Intel refers to it as "speed".

I doubt there would be any noticeable difference between cpus when using the same memory modules unless you ran an application capable of saturating the 2gt/s memory bus...something like a long duration video edit might show some improvements in rendering times with the 4gt/s bus width. A gamer or business user running lite to moderate workloads would not likely see a noticeable difference between the two if everything else in the PC is equal.
 
Apr 6, 2021
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It would be better to think of it as more bus "width" means more memory supported...that's what the 2gt/s vs 4gt/s really indicates although Intel refers to it as "speed".

I doubt there would be any noticeable difference between cpus when using the same memory modules unless you ran an application capable of saturating the 2gt/s memory bus...something like a long duration video edit might show some improvements in rendering times with the 4gt/s bus width. A gamer or business user running lite to moderate workloads would not likely see a noticeable difference between the two if everything else in the PC is equal.
True, more bus width has a meaning towards more memory support.
As intel product page says memory of 32gb vs 64gb vs 128gb for 2gt/s vs 4gt/s vs 8gt/s but these values are more close to bus width rather than processor bus speed. And both are two different terms (speed vs lanes).
So maybe i am wrong but in my opinion bus speed is better indicating performance any how.
 

hotaru.hino

Respectable
Higher bus speed is not indicative of higher performance. It depends entirely on how much the CPU needs. As an example, a two core processor isn't going to consume and produce as much data as a Threadripper, so throwing it on a high speed bus to satisfy the Threadripper won't do anything for the two-core.

If it were between two processors of the same family, you could make the argument, but I would say it depends on the benchmarks. Some times it ships with an overkill bus speed, some times it doesn't. For instance, video cards of the lower end can get away with 4 or 8 PCIe lanes and sometimes they ship with that configuration, but sometimes they ship to use more even though they don't need it.
 

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