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I may be missing something, but I have a P4 530J 3.0GHz HT and it has a 800MHz FSB. In Everest it is saying my CPU FSB is 200MHz. Like I said, am I missing something here?
 

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200MHz is the external system bus. The total front side bus is that x4, 800MHz. When overclocking you increase the "FSB" which is the external system bus. The names mean nothing any more...
 

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I don't know what everything is called, or what everything does really, hopefully more answers to this thread will enlighten me, but here is how I see it:

The FSB that Everest shows as 200mhz is the speed of everything connected to the motherboard, except that which is locked(PCI slots, AGP, etc.) The FSB x the CPU multipler = the clock speed of your processor.

FSB as advertised on the box of your CPU is the HT multiplier x the FSB. This should never exceed 800mhz(as advertised), if you want it to be stable.

Hopefully someone else will explain the function of the FSB as advertised as 800mhz.
 

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Discussion Starter #4
Quote:


Originally Posted by YiffyGriffy

200MHz is the external system bus. The total front side bus is that x4, 800MHz. When overclocking you increase the "FSB" which is the external system bus. The names mean nothing any more...

Why is the total front side bus 4x the external system bus?
 

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Because Intel uses a technology that "quad-pumps" the data, allowing four packets to be transferred across the bus every clock cycle, thus creating a x4 multiplier. HyperTransport works in a similar way on AMDs too, I believe.
 

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Quote:


Originally Posted by amped

I don't know what everything is called, or what everything does really, hopefully more answers to this thread will enlighten me, but here is how I see it:

The FSB that Everest shows as 200mhz is the speed of everything connected to the motherboard, except that which is locked(PCI slots, AGP, etc.) The FSB x the CPU multipler = the clock speed of your processor.

FSB as advertised on the box of your CPU is the HT multiplier x the FSB. This should never exceed 800mhz(as advertised), if you want it to be stable.

Hopefully someone else will explain the function of the FSB as advertised as 800mhz.

The 800 MHz FSB on an Intel can't be compared to the HTT on an AMD system. As is stated in the thread, the 800 MHz is simply the 200 MHz external clock on the system x4 for the quad pumped architecture Intel uses. As you overclock this type of system, the FSB can be pushed to 1000 MHz and beyond on a good system with proper cooling.

As you mentioned, most everything in an Intel system runs off of the external clock except those items which are locked. It's very important to lock PCI and AGP frequencies as those get unstable very quickly when overclocking (typically 10% or less overclock will be unstable on unlocked PCI/AGP).
 
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