Dumb Qustions regarding P4, sorry usually build amds

[bob4432]

1. 400MHz FSB = PC 1600, 533MHz FSB = PC2100? 800MHz FSB = PC3200? is this correct?
2. Which chipset is the most stable?


i have 1.25GB of pc2100 laying around and want to use it, want p4 because of superior encoding performance.

thanks

 

[Soulkeeper]

you can pick up a new motherboard that supports all the old socket 478 processors and slower ddr memory
the i875 chipset is good and the i865 is the cheaper non dual channel version
then if you want you can always upgrade the memory later
you'll just have to run a memory/fsb ratio in the bios so make sure you get a board that supports this

 

[bob4432]

thanks for the response, are my memory fsb/memory numbers correct? with pc2100 can i run a 533MHz fsb chip?

 

[Budman]

Originally posted by: bob4432
thanks for the response, are my memory fsb/memory numbers correct? with pc2100 can i run a 533MHz fsb chip?

With a memory devider you can even run a 800fsb chip with pc2100 ram .

and if you want good encoding speed you'll need a HT enabled 800fsb chip.

 

[bob4432]

what is a memory devider?

 

[Budman]

Originally posted by: bob4432
what is a memory devider?

With 1:1 ram is same speed as Fsb
with 5:4 cpu at 200mhz = ram at 166mhz (pc2700)
With 3:2 cpu at 200mhz = ram at 133mhz. (pc2100)

 

[fredtam]

Originally posted by: bob4432
thanks for the response, are my memory fsb/memory numbers correct? with pc2100 can i run a 533MHz fsb chip?

Yes you can run a 533Mhz chip with 2100. The bandwidth will be matched. This isn't a new purchase is it?

i865 is the cheaper non dual channel version

The 865 is dual channel. It is the same (for all intents and purposes) as the 875 chipset. The 875 boards usually have a larger feature set. The only difference is you will lose the "PAT" capabilities on an 865 board if you change memory ratios. That is of course unless you have an Intel board which never enabled "PAT" on the 865 chipset.

 

[bob4432]

Originally posted by: fredtam

Originally posted by: bob4432
thanks for the response, are my memory fsb/memory numbers correct? with pc2100 can i run a 533MHz fsb chip?

Yes you can run a 533Mhz chip with 2100. The bandwidth will be matched. This isn't a new purchase is it?

i865 is the cheaper non dual channel version

The 865 is dual channel. It is the same (for all intents and purposes) as the 875 chipset. The 875 boards usually have a larger feature set. The only difference is you will lose the "PAT" capabilities on an 865 board if you change memory ratios. That is of course unless you have an Intel board which never enabled "PAT" on the 865 chipset.

yes this will be a new purchase minus the ram. i figured if i got a 533MHz/p4 3GHz chip and a decent motherboard this would be a better system than what i have - xp2000 w/ 1GB ram. my current system is good for me and what i do but i would like a bit more speed than a xp2400, especially for the video encoding and didn't want to buy 1GB of pc3200 since this upgrade will last me atleast 12-18mos.

do the memory deviders hinder performance? i have noticed that the better p4 boards support 800MHz and the 800MHz 3GHz P4s are pretty close to the same price as the 533MHz ones.

 

[fredtam]

The divider will hinder performance only in the fact that yoor memory will be the limiting factor in your system. Odds are however you will not max out the bandwidth allowed by the 2100. My advice is to get an 800Mhz chip and an Abit IS7. Then use the divider to adjust for your slower memory. What is your budget?

 

[bob4432]

for the chip and board - ~$300. already have everything else.

 

[bob4432]

another dumb question - where do i get these dividers and do they effect reliability?

 

[Twsmit]

Originally posted by: fredtam
The divider will hinder performance only in the fact that yoor memory will be the limiting factor in your system. Odds are however you will not max out the bandwidth allowed by the 2100. My advice is to get an 800Mhz chip and an Abit IS7. Then use the divider to adjust for your slower memory. What is your budget?

I second that, get a 2.4C and a i865 mobo.

 

[fredtam]

I second that, get a 2.4C and a i865 mobo.

2.8C would be the sweet spot at only a couple dollars more than the 2.4c and no significant performance difference between the 3.0 and 2.8.

another dumb question - where do i get these dividers and do they effect reliability?

No , they will not affect reliability. You are simply telling the pc to run the chip at its rated speed and the memory slower. The dividers are located in the bios.

A 2.8c and a Abit IS7(probably the best 865/875 board) would be the best combo for you. In 12-18 months there will still probably be nothing that really stresses a 2.8. If there is upgrade the memory and OC. It is not uncommon for 2.8s to reach 3.5GHz.

 

[SilentRunning]

Originally posted by: bob4432
another dumb question - where do i get these dividers and do they effect reliability?

Memory dividers are part of the bios

 

[bob4432]

this board?

 

[bob4432]

please bear with me, i feel like a rucking fetard about this, i went into the bios on the board i have now - biostar m7ncdpro (nvidia2 ultra400) and can't find anything regarding a memory divider. is it called memory divider in the bios?

 

[fredtam]

Originally posted by: bob4432
this board?

No this board. or this board which is basically a newer version of the IS7 with more enthusiast features.

The board you linked to is fine but does not have the same upgrade possibilities ie sata/ raid and no firewire. There is no reason to limit upgrade choice and have no firewire to save $10 since it fits in your budget.

 

[bob4432]

thanks

according to the benchmarks i have read, i should get ~50% increase in encoding with a 2.8cP4 over a athlon xp 2000. that would be nice

 

[fredtam]

Originally posted by: bob4432
please bear with me, i feel like a rucking fetard about this, i went into the bios on the board i have now - biostar m7ncdpro (nvidia2 ultra400) and can't find anything regarding a memory divider. is it called memory divider in the bios?

The memory settings on your current board are found under "Advanced Chipset features" as "memory Frequency" and are listed as percentages rather than the ratios you will see on the IS7 ie. 1:1, 5:4, and 3:2.

 

[fredtam]

Originally posted by: bob4432
thanks

according to the benchmarks i have read, i should get ~50% increase in encoding with a 2.8cP4 over a athlon xp 2000. that would be nice

Remember you may lose some of that speed because of your memory bandwidth. Also is your current memory the same make, spped, and timings to allow for dual channel operation?

 

[bob4432]

i run it in dual channel now with the settings set by spd. i don't overclock at all, very conservative settings.

i will have to read again and see where the memory speed makes such a big difference.

so the 800MHz/2.8c chip will still run at 2.8GHz, but the link to the memory will be cut down to 133MHz instead of 200MHz? am i following this correctly?

i actually just cut the memory down to 106MHz and don't notice any difference. i will game a little later tonight to see if it makes a difference there.

thanks all, i am learning so much

update - gamed -> bf1942 - didn't notice any significant changes to my eye, a benchmark may tell differently...

 

[fredtam]

so the 800MHz/2.8c chip will still run at 2.8GHz, but the link to the memory will be cut down to 133MHz instead of 200MHz? am i following this correctly?

You are correct. You may not notice it all unless you use an application that will use more than the bandwidth provided by 2100 but I can't really give you an example.

 

[bob4432]

even though the specs on those m/b s says the ram needs to be 333/400, the 2100 will work?

 

[Tab]

Another dumb question, how do these memory dividers actually work? Mathmattically?
Why does overclocking interfere with a Non-locked PCI Bus?

 

[InlineFive]

Originally posted by: Tabb
Another dumb question, how do these memory dividers actually work? Mathmattically?
Why does overclocking interfere with a Non-locked PCI Bus?

1. Yes. It allows processors and memory at different speeds to work with each other. For example an 800Mhz processor could be used with PC2100 memory without a problem with the 3:2 divider. So you take the P4 bus (in this case 200Mhz) divided by three times two to yield a 133Mhz memory bus. Likewise if you used a 5:4 divider on a 200Mhz FSB processor the memory would run at 160Mhz.
2. Overclocking will interfere because some components can't run above the stock PCI speed of 33.33Mhz. Raising the processor bus will also raise the PCI and AGP bus' on a non-locked board. This is why locked PCI-bus boards are very desirable by overclockers.

-Por