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[oc-lord]

Registered
Joined
May 23, 2003
Location
belgium
why is it better to have a lower multiplier(f.e: 2.66Ghz533 @ 20x)?
is it because you can overclock the fsb then higher? please let moe know. (i'm planning to buy an 2.66Ghz533 for use on an asus p4b533(max multiplier= 24x)with 2700 ddr. pci and agp are locked on 33/66 so that wont be the problem to oc. i hearded that the 2.4b is a better overclocker than the 2.66b so it it true or not.
 

micamica1217

Member
Joined
Jun 1, 2002
well you can't go wrong with both of the cpu's that you mentioned.
yet the newer 2.4b's seem to OC to very nice numbers.

even if you get a "bad" 2.4b, you should be able to hit 3.2ghz.
about the same place you'll get with the 2.66.
I just havn't seen many 2.66 OCed rigs..some do great, and some poor.

one thing I noticed is that you''l be using pc2700...
with only a 3/4 mem ratio on the mobo, you may be better off with the 2.66
yes, I'm sure you'll be able to OC that memory a little...
but I can't say how much.

if you didn't buy the memory yet, think about pc3200...
you'll be able to OC higher and still have great mem bandwith.
it's not much more money to buy a cheap stick of pc3200.
just look around newegg.com or googlegear.com

anyway, good luck

mica
 

batboy

Senior Moment
Joined
Jan 12, 2001
Location
Kansas, USA
It might not "officially" support PC3200, but it will work ok. My mobo only supports up to PC3200 and I'm using PC3500 in it. Our CPUs don't "officially" support overclocking either, but we still do it. PC3200 will work in your mobo, trust me.
 
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[oc-lord]

Registered
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May 23, 2003
Location
belgium
my mobo only supports officially 1600 and 2700 and it would unofficially do pc2700 (i also seen people running it on a p4b533 mobo stable), but it wont support all types of pc3200 ( i know people who have problems with it), so i think i would stick with the pc2700 (why would it be better with the pc3200? do i get my fsb higher and if it does how high, and would my cpu be stable @ that fsb?)
 
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[oc-lord]

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May 23, 2003
Location
belgium
oh yeah my mobo uses @ a fsb higher than 133 only the 1:1 mem ratio (under the 132 it uses 1:1 and 3:4) but i can make it do 3:4 with the dipswitch-6 trick (it then uses the 3:4 above 133) but would it not be better if i use the 4:3 ratio (f.e if my ram runs @ 166fsb then my cpu clockspeed is 221) and i heared that people can't get their fsb any higher than 170 with the p4b533. is this true and why? (is it you mem that holds you back or is it the cpu that doesnt support such a high fsb)
 

micamica1217

Member
Joined
Jun 1, 2002
oc-lord,

you want to use the 3/4 ratio for added bandwith and yes this makes your cpu faster.

you may want to test your system at 4/3 and 3/4 with many tests that you'll use your rig for.
then run at the ratio you'll do better at.

I feal this will be with the 3/4 ratio.
I know it was always 3/4 or 4/5 ratio for me, on my old P4PE.

mica
 
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[oc-lord]

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May 23, 2003
Location
belgium
ok but how far do you guys think i can get my fsb wit the pc2700 no matter how my memratio is configured(what willbe the cpu speed if i use the 2.66b)
 

tread70

Member
Joined
Jul 15, 2002
Location
SC
I say get the pc 3200 even if you dont use the memory bandwidth it is capable of , in order to OC the cpu the highest you can go you would have to relax the mem timings to achieve it. If you buy the 3200 and run at say 3000 speeds you can do it with confidence at the tightest timings for increased bandwidth. It will just give you more headroom on the OC and you wont be limited by the memory holding you back. I know the 2.4b will take you up to say 170-180 fsb if you use 175 @ a 1:1 ratio that will be ddr350 not sure if your 2700 will do ddr350 and if it does then it will be at the most relaxed timings say 2.5/3/3/7, but if you use 3200 you can easily do ddr350 @ 2/2/2/5 for the increased bandwidth/faster speeds ,it is worth it. I personally would take BB and Mica's advice and get the higher speed memory just so that you have an easier OC, I dont believe you will regret the decision on purchaseing the higher speed ram.
Tread
 
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[oc-lord]

Registered
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May 23, 2003
Location
belgium
mmm but if i would let my cpu run at normal speed , my ddr would run @177 (133/3*4=177 with 3:4 ratio) so that is to slow for pc3200/400 but if i take the pc 2700/266 i could let it run @ normal speed with the 1:1 ratio and if i oc ill get the fsb up to 182mhz max. so my cpu would run @3.64hz so that is a great overclock.
 
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[oc-lord]

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May 23, 2003
Location
belgium
and i only have the 1:1 and the 3:4 (unoficially supported above 132 mhz with the dipswitch trick) mem ratio so the pc 3200 would be underclocked
 

micamica1217

Member
Joined
Jun 1, 2002
ok, let me explain further.....

your cpu wants or better yet, needs, more memory speed then you will ever be able to give it on the mobo listed above.

infact, at 133fsb you will need to run the memory at 4x the FSB speed to get the "full" performance of the cpu.
in other words you are running a 533 bus cpu, but with pc2700 and the 3/4 ratio at 133fsb, your mem speed will be 354 (bus).

as you can see, your memory is just not fast enough to keep up with the cpu speed. and on this mobo, like all sigle DDR mobos, it never will.
now, this is the result, when not OCing at all.
and yes, your memory is at it's max speed already.

you could OC the cpu and use the 1/1 ratio...your results will be that you can get the cpu up around 166fsb, but your mem speed never increases in any way...thus you loose even more bandwith,
and while your now OCed system is faster then stock, I'll bet it's not by much.
this will be about the max OC you'll be able to do with the memory you picked out.
yes you may be able to OC the memory some, but how much???

if you will be able to use the 4/3 ratio, then yes you can OC the cpu to say a higher fsb if the cpu will let you.
yet your cpu bus speed is far higher then you mem bus....thus you may not see any large increase in speed then running at stock and 3/4 ratio.

with faster memory, you'll have more options to OC higher as well as have more bandwith at a time when you'll never have enough.

it's now time to start reading some of the old posts here.
it seems that you may think that just increasing the FSB is all it takes to have a faster system. this is only half true.
your memory speed needs to get faster as well.

yet what your saying is that you want to OC the cpu but keep the mem speed the same or lower as you get higher and higher on the FSB.

mica
 

batboy

Senior Moment
Joined
Jan 12, 2001
Location
Kansas, USA
Mica is right. Let me see if I can explain it a little differently.

Here's the situation. On average you can expect the 2.66 to hit 160 FSB or 3.2 gig (you might get luck and get a better overclock). You only have two mem ratio options (1:1 or 3:4). You want the highest CPU clock speed AND the highest RAM speed for the best performance. So, 160 FSB using the 1:1 ratio will give you DDR320, which is a good match with your PC2700 RAM. If you're on a tight budget and already have that RAM, then go for it.

If you need to buy RAM too and can scrape up a little more cash, then buying faster memory is a good thing and really improves performance. Check this out, 160 FSB using the 3:4 ratio gives you DDR427. Now you need PC3500 to be able to run at aggressive timings (some good PC3200 RAM can do this too). In this example the CPU clock speed and FSB is the same, but the 3:4 ratio DDR427 will kick butt on 1:1 ratio DDR320. Go for the faster RAM if possible.
 
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[oc-lord]

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May 23, 2003
Location
belgium
ok thanx guys you really teached me something about having better ram in your oc'ed system. but will my mobo support this type of ram i've heared that people have problems with this type of ram on the asus p4b533 mobo (with a corcair stick(i dont know the link anymore, but its on the intel mobo / asus forum)) and if i want to run the system @normal speed would this be possible whit this type of ram

(i checked the store where im planning to buy my parts and they have ram-sticks of: (they have other types also)

DDR PC400/PC3200 GeIL 256MB CL 2.5
@€65

DDR PC400 - Corsair XMS LL 256 CL2 CMX256A-3200LL
@€115



im planning to buy the first one (i only have a small budget and people had already had problems with the corsair xms on this type of mobo)

would this be a good choice? let me know
 
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[oc-lord]

Registered
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May 23, 2003
Location
belgium
oh yeah mica do you have any teachfull links about oc'ing and the "memory"

thx for your help already
 

batboy

Senior Moment
Joined
Jan 12, 2001
Location
Kansas, USA
Geil seems to work good up to it's rated specs, but "often" don't like to be overclocked. If you're getting PC3200 RAM, you'll want to be able to overclock it a little. I like Corsair better and it's proven to be a good overclocker. However, I understand your reluctance to buy it if others had trouble with Corsair on your mobo. I have heard some mobos don't like the Corsair LL series (LL=Low Latency). See if they carry the regular XMS series or maybe look at Kingston HyperX or TwinMOS.
 
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[oc-lord]

Registered
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May 23, 2003
Location
belgium
IMPORTANT QUESTION BEFORE I BUY THE PC 3200)

and say i buy a p4 2.66 with pc 3200 256mb ddr (GEIL) and i put my system together would it work if i press the power button and would it continu workin non-oc'ed (pc 3200 @ fsb of 133)
 
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[oc-lord]

Registered
Joined
May 23, 2003
Location
belgium
or is it better to buy the pc 2700 to have not mutch problems (remember: i'm a beginner, and dont want to much trouble with my first good oc)