Building new rig and confused...

I am currently running a p3 1.0 with 512mb pc133, so its time to upgrade...ive looked into almost everything possible. i have never oc'd a cpu b4 aside from the fact that my friend oc'd my pentium 200 to 233 with a simple jumper switch lol. anyways, i have looked into amd 64's intels p4 northwoods/prescotts/478/lga options. i am considering overclocking my new computer. i have been doing a lot of reading on this forum and gaining a load of information. i would like to stick with intel if at all possible although i know some ppl believe amd is oc king. i am concerned about heat issues and instability. i am not looking into putting a lot of money into this comp but here is what i have come up with. I want around a 3.2 whether it be a prescott or northwood. i have heard some things that concern me about the "preshotts". i dont now want to have to purchase water cooling or some expensive form of cooling but am willing to put a little money into a better heatsink/fan if i do oc. i was looking into the asus/msi/soltek boards but dont really know the best...i know that intel has a nice board but all i hear is that with intel boards...good luck with a nice oc. i am thinking i would like the 875p chipset, i have done my research on the 925x as well and it seems that pci-express is not putting up impressive enough numbers to spend more money for that setup. i was thinking about going ocz for ram too bc i have seen some nice benchmarks and heard some good things about them. now the one thing that i would like to be cleared up on is the ratios. i have read about the 1:1 and the 5:4. meaning fsb to ram ratio. now i understand that both cpus i listed run at 200mhz (200x4). now one thing that i do not really understand is what are the guidelines to increasing the fsb. i mean can you say hmm i would like it to be 213, or does it have increments it goes by. i know that fsb x multiplier = cpu speed...i would like to take a 3.2 with a 16 multiplier and raise the fsb to 250 making it right at 4.0ghz. i know that with a 250fbs a 5:4 ratio would work with pc3200 (200mhz), but is a 5:4 always stable? is a 1:1 always stable? is there just a place in the bios to where you can change the fsb or the bus on ram to any value you would like? and im also a little sketchy on the voltage to cpus. any advice or explanations would be greatly appreciated. thnx in advance.

Whoa dude, slow down. You have'nt even got the parts yet and your shooting for a ragged edge system. If this is going to be youur main rig, then start out at stock speeds, and then baby steps. 3.2 is 2.2 faster than what your running. Get the correct ram for what your shooting for, and a good HSF like a TT Polo735, and slowly work your way up, doing a lot of stability testing after each step. SO you don't end up with an expensive doorstop. And keep your present rig as a backup , if things don't work.

Not trying to be sarcastic but its almost impossible to tell if a computer thats isnt even built yet will be stable when overclocked.
Since you seem to be concerned with heat issues Northwood core might be a better choice.
As for setting the FSB and the increments you set it by, that depends on the motherboard. But most motherboards ecspecially ones geared for overclocking will let you input cpu FSB in incrememnts of 1. I have a DFI 865PE Infinity and its an overclockers board. For my cpu, which is an older 2.4B Ghz cpu, the bios allows me to set the fsb anywhere in increments of 1 from 133 to 200. And as you stated this fsb or system clock number is then multiplied by the cpu's multiplier to get the cpu speed. So yes alot of boards will allow you to put fsb at say 213. My fsb is set at 150 (4 X 150 = 600Mhz FSB).
I kind of doubt 4.0Ghz is possible on air cooling.
Also increasing voltage to your cpu will increase cpu temps.
ALso you might want to consider the cheaper 865PE chipset. It is very similar to the 875. Also there are motherboard manufacturers that have enabled the Memory enhancement feature in the 865PE chipset that Intel disabled making it even more similar to the 875 but for a lower price.

ok, so say i have a p4 3.2c and i have a 875p chipset mobo that allows increments of 1 to overclock my fsb. say i overclock my fsb to run at 213. well, at a 1:1 ratio that would be a 213:200 if i was running pc3200 ram. the numbers dont match =\ and even with a 5:4 it would come out being 213:170 and my ram wouldnt be running at 170 it would be running at 200. i guess what im trying to say here is that for a 1:1 or a 5:4 do the numbers have to match exactly for there to be a stable system or is there more to it than that? can it be say 213:200 and still work? or would i also have to adjust the bus on my ram? thnx.

1:1 ratio means that the cpu fsb is running at the same speed as your memory. This is called running in sync(syncronous). So if u have ur cpu set at 213 (4 X 213 = 852Mhz FSB). Since we have a 1:1 ratio our ram is now also running at 213 instead of 200 so that gives us 213 X 2 = 426Mhz. So our ram is also overclocked (assuming its DDR400 PC3200).

so then what you are saying is that no matter what i decide to change my fsb to, it will automatically overclock the bus speed of my ram? or do i actually have to do that manually? thnx for replies

No, changing cpu bus speed doesnt always overclock ram. Some motherboards have a divider setting where you can overclock cpu and leave ram at a certain speed. 1:1 will more than likely give better performance. There are other ratios like 1:1, 3:2, 5:4.
Here is my computer running a 1:1 ratio. I have a 2.4B Ghz P4. Stock fsb is 133 X 4 = 533Mhz. My cpu fsb is set to 150, so 150 X 4 = 600Mhz. Since the cpu to ram ratio is 1:1 they will be running in sync together so the ram will also be 150. Since its DDR ram we multiply that times 2, so 150 X 2 = 300Mhz.

Here you can see my cpu's fsb and core speed:


Here is my memory and my cpu to ram ratio:

Here I have a 4:5 ratio. The cpu fsb is still at 150, but the ram has been moved up to 188.

The cpu:


The memory and the new ratio:

isnt pc3200 ram supposed to run at 200 default? since you only had the 133mhz fsb chip did you have to underclock your ram to 150 to be in sync with a 1:1? if so, should i be able to safely run a p4 3.2c at 4ghz since that would only require upping the stock fsb from 200 to 250 and running a 5:4 ratio with my ram still running at 200? or would i have to oc my ram to 250 as well to make it more stable? i am thinking about buying ocz ram bc i have heard good things about them in the overclocking world. i know that if i wanted a 1:1 with my fsb running at 250 then i would need pc4000 ram...but i dont think there are any mobos with a d875p chipset that will take pc4000, unless you know of any? if i could do that how do you think that setup would run at a 1:1? i also do not understand what increasing/decreasing the timings on ram does, say 2.5-4-4-6? any advice is appreciated. thnx for help. nice screenies too

Just about every 875P chipset motherboard out will take PC4000 RAM.

Im going to clear a few things up, but not in order. First, your question about timings. Lower timings=better performance per clock. 200mhz with say, 2-2-2-6 might be faster than 210@3-3-3-8.

For a 533FSB chip you do have to underclock your ram, unless you run the ram faster than the fsb.

If you were to get to 4ghz(not likely, think 3.6) then you could either run your ram at 250 or 200, whatever you choose. They have ram dividers so you can save money on ram in your pc. Dell puts PC2700 in their P4c systems and uses a divider. Keep in mind that PC3200 can run over 200mhz, it will just need looser timings/and/or/higher voltage.

I personaly havnt used OCZ, but everyone likes it. I use buffalo and it overclock pretty well. My cheep-o buffalo PC3200 did 245fsb with 2.9v(which is safe. Stock is like 2.6, many people go to 3.3 or more).

On a side note, you might also be happy with an AMD64 system. I got mine recently, and it seemed quite tricky to overclock, but it was just an appearance. At 1.8ghz(AMD64 2800+) my cpu performs on par with an Athlon XP at 2.4ghz(about a 3500+) or a P4 at 3ghz. If you do a lot of gaming then the 64 is exactly what you need.

my ram (kingston calles it pc3000, but cpuz says its pc2700) will do 226mhz at 2-2-2-5, on 3.0v. my bios allows up to 3.2, but my board has a problem with vtt with it set that high. really the most i can use effectively i'd say is 2.9. there is a mod to fix it, but i haven't had the time to get down to it. i've seen many ppl run my ram at 240+ 2-2-2-5 after getting motherboard voltages fixed.

basically, if you are planning on running a 5:4 ratio, you want ram like mine. ram that will run at the tightest timings possible (2-2-2-5) since you won't see more than 200mhz out of them. this is FAR cheaper than going pc4000+, and yields pretty good performance.

you definatly wont get 4ghz by "just putting a little money into the heatsink/fan" remember the higher you increase the FSB the higher you must also increase the Vcore (voltage to the cpu) to maintain stability...and as you might have guessed increasing power also increases heat...just keep that in mind before you go pumping up the vcore and fsb.

xtasy22 said:

isnt pc3200 ram supposed to run at 200 default?

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Yeah stock speed for PC3200 is 200Mhz.

xtasy22 said:

since you only had the 133mhz fsb chip did you have to underclock your ram to 150 to be in sync with a 1:1?

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Yeah kind of. My cpu multiplier is 18. So if I had my PC3200 ram at 200 with a 1:1 ratio then that would mean my cpu's fsb would be 200. CPU core speed is the cpu fsb * multiplier. So that would have been 200* 18 = 3600. Kind of high, and I dont want to have to bring my voltages that high cuz I only got a stock heatsink fan.

xtasy22 said:

if so, should i be able to safely run a p4 3.2c at 4ghz since that would only require upping the stock fsb from 200 to 250 and running a 5:4 ratio with my ram still running at 200?

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Kinda of hard to predict stability. Depends on your temps, cooling, bios settings, etc. Buts its sure not impossible.

You won't get 4 GHz, at least not without very good cooling and lots of volts.

You seem to at least understand most of what overclocking involves which is good. But don't get ahead of yourself yet. Once you have the system just take it bit at a time.

If you pick up some RAM that will do around 230 MHz FSB then with a 3.2 GHz P4 you should be at 3.68 GHz which is decent enough. That is with a 1:1 ratio. That is a sort of achievable target.

For the motherboard I would get an Abit IC7 (preferably the MAX 3 version) for the P4. But I wouldn't rule out AMD yet either. Thermalright heatsink.