Intel always has a Bus Speed of 100mhz

[ZoneDymo]

Just a question out of curiosity, why do all Intel cpu's have a bus speed of 100mhz and then are overclocked by the multiplier.
My 2600k has it and the upcomming 11900k has it, why?

Im not saying its bad, just strikes me as odd, what does bus speed do? would there be a benefit to having iy run at 200mhz but is that just not doable?

 

[INSTG8R]

So does AMD nothing really strange here?

 

[hat]

I think it's just a common, easy to use number. As far as I know, that "bus speed" doesn't actually run anything... it's just a number to use as a base for the multiplier on everything else. Core speed, RAM speed, and whatever else.

 

[Solaris17]

Just a question out of curiosity, why do all Intel cpu's have a bus speed of 100mhz and then are overclocked by the multiplier.
My 2600k has it and the upcomming 11900k has it, why?

Im not saying its bad, just strikes me as odd, why does bus speed do? would there be a benefit to having ti run at 200mhz but is that just not doable?

we've done it lads, we now live in a time where people dont remember multiplier locks and FSB clocking.

 

[phanbuey]

I think it's just a common, easy to use number. As far as I know, that "bus speed" doesn't actually run anything... it's just a number to use as a base for the multiplier on everything else. Core speed, RAM speed, and whatever else.

This - it's 100mhz, but that's sort of a made up number --

2600K bus speed:

sky/kaby/coffee/lava lake bus speeds:

we've done it lads, we now live in a time where people dont remember multiplier locks and FSB clocking.

I still remember when it was imperative to buy the old pentium II/celerons with the 66Mhz bus just so you could jump em to 100mhz on the mobo with their locked multies...

those were the days. Also still remember that Solaris Utility DVD i had laying around ...

 

[hat]

we've done it lads, we now live in a time where people dont remember multiplier locks and FSB clocking.

Sadly, now they're both locked... unless you pay a hefty premium. I could see myself getting a 10100 if I could push it to 5GHz or beyond.

 

[Bones]

we've done it lads, we now live in a time where people dont remember multiplier locks and FSB clocking.

Looks that way but luckily I still remember.
Intels from Socket 775 and back run at 200 FSB/BCLK by default, the change was made to 100 about the time when Sandy Bridge was introduced back in 2010/2011.

As for advantage, there is in that you have more room to get things dialed in exactly where they would be optimized, mainly with RAM speeds.
By that I mean you can zero in on the best speed for your sticks and adjust system speed with a combination of CPU multiplier and FSB speed.

 

[newtekie1]

AFAIK, the PCI-E bus runs at 100MHz, so thats why the BCLK is 100MHz.

 

[RJARRRPCGP]

I remember the days, where 133 seemed to be their favorite number!

 

[Deleted member 202104]

we've done it lads, we now live in a time where people dont remember multiplier locks and FSB clocking.

That feeling moving the FSB from 66MHz to 100MHz on a Celeron 300a... 450Mhz of pure power.

 

[freeagent]

Its better than 99.8MHz lol. Certain multipliers sit better than others. x46 was always 4600 for me, x45 was always 4498.5 or whatever lol. x47 was 4697.5 but x48 was 4800. I don't know maybe I'm crazy. But was usually within half a tick

 

[Zach_01]

AFAIK, the PCI-E bus runs at 100MHz, so thats why the BCLK is 100MHz.

Don’t count on it...
Older AMD systems had 200MHz base clock but a 100MHz PCI-E bus speed. There are multies and dividers on a system.

 

[RJARRRPCGP]

Its better than 99.8MHz lol. Certain multipliers sit better than others. x46 was always 4600 for me, x45 was always 4498.5 or whatever lol. x47 was 4697.5 but x48 was 4800. I don't know maybe I'm crazy. But was usually within half a tick

Reminds me of my Conroe E4500 on my Asus P5QL Pro (P43) motherboard, where 333x9.0 was 2997 Mhz, lol
While my Asus Maximus II Gene (P45) motherboard, albeit I never used the E4500 in it, (because I already had a 45nm Core 2 Duo by that time) would actually be 333.33333333333333 or the like for the FSB frequency.

Does anyone here think that was spread-spectrum causing the lower FSB clock on my lesser-model motherboard?

 

[Jism]

AMD's base clock is also 100Mhz, however it's so wide that it's more then enough bandwidth available compared to CPU's from 20 years ago.

 

[Zach_01]

Reminds me of my Conroe E4500 on my Asus P5QL Pro (P43) motherboard, where 333x9.0 was 2997 Mhz, lol
While my Asus Maximus II Gene (P45) motherboard, albeit I never used the E4500 in it, (because I already had a 45nm Core 2 Duo by that time) would actually be 333.33333333333333 or the like for the FSB frequency.

Does anyone here think that was spread-spectrum causing the lower FSB clock on my lesser-model motherboard?

The 99.8MHz is not an indication of low grade board. Even 500$ boards do that. Usually when you disable Spread Spectrum you get an even 100MHz. Mine does it too (X570 AorusPro) and I keep it disabled.

AMD's base clock is also 100Mhz, however it's so wide that it's more then enough bandwidth available compared to CPU's from 20 years ago.

Also, the idea and characteristics of FSB has died a few years back. Its mostly PCI-E interconnection now (X lanes) and base clock is just a clock for the various subsystems to run at with multies.

 

[Jism]

Does anyone here think that was spread-spectrum causing the lower FSB clock on my lesser-model motherboard?

Yes, spread spectrum could affect the FSB and such, and was always recommended to turn off the moment you start to overclock. However spread spectrum was advised when working or being in area's where's lots of EMI or so. It's an additional layer to prevent strange things happening to your data or running computer.

Also the idea and characteristics of FSB has died a few years back. Its mostly PCI-E interconnection now (X lanes) and base clock is just a clock for the various subsystems to run at with multies.

It did'nt die.. You can still "overclock" using the Bclk, which can boost stuff tremendously. It can even increase the maximum boost clock your CPU is ticking at. I remember having a FX8320 while raising the FSB from 200Mhz stock to 300Mhz or even beyond yielded even better performance then a higher clocked CPU. A 4.8Ghz 300Mhz FSB FX was "better" then a 5Ghz or even 5.2GHz FX using a stock FSB.

Even 386's and 486's yielded great increase in performance by raising the FSB.. some socket 7 boards went all the way up to 83Mhz.

 

[Zach_01]

Yes, spread spectrum could affect the FSB and such, and was always recommended to turn off the moment you start to overclock. However spread spectrum was advised when working or being in area's where's lots of EMI or so. It's an additional layer to prevent strange things happening to your data or running computer.



It did'nt die.. You can still "overclock" using the Bclk, which can boost stuff tremendously. It can even increase the maximum boost clock your CPU is ticking at. I remember having a FX8320 while raising the FSB from 200Mhz stock to 300Mhz or even beyond yielded even better performance then a higher clocked CPU. A 4.8Ghz 300Mhz FSB FX was "better" then a 5Ghz or even 5.2GHz FX using a stock FSB.

Even 386's and 486's yielded great increase in performance by raising the FSB.. some socket 7 boards went all the way up to 83Mhz.

You have missed the point completely I'm afraid, and I know what BCLK is and how affects all others. I did say that all subsystems relay on BCLK with multies, didnt I? Have you missed that one also?
The FSB(the main clock of 100/133/200/266/333MHz) of the old systems and todays base clock (100MHz BCLK) is two different things. There is no FSB bus today like the old days.

 

[Bones]

AFAIK, the PCI-E bus runs at 100MHz, so thats why the BCLK is 100MHz.

I'm afraid that's not correct.
Even systems using the older standard of FSB being 200, PCI-E is still at 100 by default with those.

 

[ZoneDymo]

we've done it lads, we now live in a time where people dont remember multiplier locks and FSB clocking.

no I do, that is what I had to do on my e6750 back in the day, my question is just why all Intel chips have that 100mhz bus speed as a base.
Why not 200 Mhz with half the multiplier? or does that not matter in any way perhaps?

I'm afraid that's not correct.
Even systems using the older standard of FSB being 200, PCI-E is still at 100 by default with those

ok well added question, why does the PCI-E slot run at 100mhz? what does that do? would anything be faster if that ran at 200mhz?

 

[Deleted member 24505]

FSB doesn't always have to be 100

 

[newtekie1]

Don’t count on it...
Older AMD systems had 200MHz base clock but a 100MHz PCI-E bus speed. There are multies and dividers on a system.

I'm afraid that's not correct.
Even systems using the older standard of FSB being 200, PCI-E is still at 100 by default with those.

Yes, and those older systems likely had an external PCI-E bus with its own clock generator. Not a PCI-E bus that originates on the CPU and using the CPU's clock generator. That's also why you can change the FSB speed on those systems without affecting the PCI-E bus speed. Intel switched to using a single clock generator with socket 1155, IIRC, and AMD did it with AM4.

I'm talking about how things are today, not 10 years ago.