533mhz Fsb

[sapiens74 0]

Does anyone know on the new P4 chipsets if you can run the bus independently of the of the Chip. So I could run my 1.8 at 533 MHZ FSB?

[Sampson 0]

I am not sure I understand what you are asking. Do you mean "can you take your present 1.8 and put it in a 533(133) motherboard?" The answer is no. This chart from Intel breaks down the FSB for P4's: http://support.intel.com/support/processors/pentium4/corespeeds.htm

A number of 100 MHz motherboards have the facility to up the FSB above 100MHz while keeping the AGP, memory or peripherals at their standard 2/3,1/2, 1/3 speeds though some can divide it with a little more sophistication. I'm certain those same motherboards companies will do the same on the 133FSB. The 533MHz actually refers to the "quad pumped" method of how the number of electrons (4) ride the sine curve, but it is still running at 133.

If you want a 533FSB you will have to get an new P4 - a 2.26, a 2.40B or a 2.53. You should be able to overclock your present machine up 2.4 or thereabouts.

[sapiens74 0]

But I can still use the same ram gotta get a new CPU then. THat's cool, I need one anyway

[CUViper 0]

For those of you who have no interest in the technical details involved, feel free to skip this post...

Quote:

The 533MHz actually refers to the "quad pumped" method of how the number of electrons (4) ride the sine curve, but it is still running at 133.

Well, yes and no. Quad pumped means that there are four data transfers in a single clock cycle. There is no sine wave involved, and if it was detecting information about individual electrons, then you're getting into quantum theory.

 

Data transfer in current computers happens with pulses. For example, the actual clock is a square wave that constantly goes from zero to one to zero to one, like this: _|¯|_|¯|_|¯. In a "normal" system, the data could be pulse-triggered or edge-triggered. Pulse-triggered means the data can be read anytime the clock is at one. Edge-triggered means the data should only be read when the clock is going from one to zero. (that's negative edge-triggered - positive edge-triggered would be when the clock goes from zero to one) These methods get one bit transfered for every cycle of the clock. DDR ram works on both the positive and negative edges, so you can send data 2 different times in one clock, for twice the throughput.

 

I'm not sure how the quad-pumped bus is actually implemented to get four bits in one clock cycle. I've seen a lot of speculation though, from having 4 separate buses, to your electron idea. It could also be that there are 4 separate trigger points in the clock cycle. Or it could be like a modem, with 16 different voltage levels to represent the state of the four bits (e.g. 0000, 0001, 0010, ..., 1101, 1110, 1111) Even on Intel's website, I can not find any specification for how it actually done, but I suspect that it is along the lines of having 4 trigger points. If anyone knows for sure or can point me to some documentation, I would appreciate it!

[Palos 0]

What bus are you talking about in the first place? The FSB? Memory?

You can certainly drop a Northwood "A" in a i845E board and "overclock" it by running at 133FSB (quadpumped 533). You could also run the memory in sync with the FSB (1:1 ratio) for DDR266 (PC2100) speeds, OR, you can run it async (133:166) for DDR333 (PC2700) speeds. Although the i845E does not officially support DDR333, it can run it for sure

 

As far as the overclocking goes, the new i845E, in the shape of the ASUS P4B533, CAN adjust the PCI/AGP/MEM ratios manually or LOCK them to 33/66/133 or 33/66/166 ! This is the best part of the deal, if you ask me

 

The question now is if your 1.8 is a Northwood or a Willamette. You can in 99.9% of the cases run the NWood at 133 FSB, giving you a 2.4GHz speed, but remember that in the case of P4 overclocking, the MEMORY bandwith is more important than the FSB increase. You will see huge differences between a P4 with DDR266 and one with DDR333, even beating the RambusPC800 in the case of DDR400

 

Here is a very good link to a board where you can find out (almost) anything on P4 overclocking and such: www.asusboards.com

Visit the forums, you'll be surprised what u'll find...

[BladeRunner 0]

You will see huge differences between a P4 with DDR266 and one with DDR333, even beating the RambusPC800 in the case of DDR400

 

But of course if you are overclocking, then your PC800 RDRAM will be running at PC1060 specifications which will once again wipe the floor with DDR.