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Is the FSB dependent on the CPU at all?

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timmyqwest

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Joined
Nov 10, 2002
Location
illinois
My instinct says no but could

chip "A" run a 220fsb
and chip "B" run only a 210fsb

with no change to the system except the CPu
 
If I understand what you're asking, you will get varying OC results depending on the chip you have (not considering any other factors). Chips from the same exact batch can vary greatly in what they can run at.
 
Exactly like he says, sometimes you just get a "good" chip, not that any are necessarily bad, but some just are better for OCing than others.
 
No...you guys are missing my point sorry...

Can one chip hit a higher FSB then the other (i'm talking AMD here where you can change multipliers)
 
The FSB is part of the chip -- there are several hundred thousand transistors devoted to doing FSB things on modern chips. So just like some chips can achieve higher core speeds than others, some can maintain a higher FSB speed than others.

That doesn't mean that the limiting factor is always going to be the FSB section of the CPU though.
 
yes it does vary, typically there will be another limiting factor but not all chips will run at the highest fsb your setup is capable of and some will take more vorltage than others to get there
 
Ok so I'm thinking that your question is asking if the FSB is restricted more by the mobo or is it possible that just switching cpus could increase FSB.

I'm gonna try and answer that, (hopefully its more what you were asking):

Basically the answer is again that it depends on the cpu, your cooling system, and the cpu multiplier.

Basically until you unlock a P4 the multiplier is fixed at ____ (23 in my case) meaning that the only way to increase the FSB is to increase the cpu clock, which raises cpu speed along with the FSB and also increases cpu temp! so this is where you need some extreme cooling, I mean yeah you could crank your p4 to 4Ghz+ and watch it die within seconds achieving a huge FSB but that doesn't make any sense. If you unlock the processor, you can change the multiplier which in turn should allow you lower your cpu speed, and make it possible to increase FSB with a lesser increase in cpu speed, which in turn lowers temperatures. I've been unsuccessful in unlocking my p4 cause I don't want to pull pins or paint them. (if anyone has suggestions on other ways to unlock a p4 3.06 northwood let me know cause I have yet to read about another way to unlock it).

Ok as for AMD pretty much all either come unlocked or can easily be unlocked, I think AMD designs there CPUs more for the OCer in that aspect... but yeah because you can change the multiplier more ore less right off the bat in an AMD, its maybe easier to get the FSB initially higher on an AMD, but who knows in the end if you have both cpus unlocked with identical cooling systems.

So unfortunately I don't think your question has an obvious and direct answer that is applicable 100% of the time.
If I understand what you're asking, you will get varying OC results depending on the chip you have (not considering any other factors). Chips from the same exact batch can vary greatly in what they can run at.
cause in the end it really depends on IF you get a "better" cpu from the batch and furthermore on the rest of your system setup.
 
timmyqwest said:
My instinct says no but could

chip "A" run a 220fsb
and chip "B" run only a 210fsb

with no change to the system except the CPu

i think that depends on how much the cpu will o/c. if the cpu is running at the same clockspeed all the time no matter what the fsb, using multis to keep it that way. then no. that would be dependant on the dividers/ram, or if there is a pci lock, then the ram, not the cpu.
 
Re: Re: Is the FSB dependent on the CPU at all?

modenaf1 said:


i think that depends on how much the cpu will o/c. if the cpu is running at the same clockspeed all the time no matter what the fsb, using multis to keep it that way. then no. that would be dependant on the dividers/ram, or if there is a pci lock, then the ram, not the cpu.

guys your making this harder then it needs to be

Running in sync with the ram...with no change to the system except the CPU.

Could one CPU potentially hit a higher FSB then another CPU...i dont care what the multipler is set to (aside from the fact that you cant change the multipler on an intel, thus ruling them out of this disucssion)
 
It sounds like this is what you're wondering:

Let's say you can lock the cpu core speed at 2000MHz, and the multiplier can be any decimal value. Assume also that the chipset and RAM can reach any speed.

CPU1 might be able to do a 237Mhz FSB (x8.44), while CPU2 might only be able to do a 229Mhz FSB (x8.73).

So yes, two CPUs can have different absolute FSB speeds. But in all likelihood, you will max-out one of the CPU core, the chipset, or the RAM first.
 
all i'm asking guys is if one chip can hit a higher FSB then the other with no change to a system other then that chip
 
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