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advanR

Member
Joined
Jun 11, 2002
Besides the memory speed and processor speed, what effect does fsb have on a system.

The reason why im asking is because i want to know why else it is good to have it high. If there isnt another reason i can buy a 1.4 gig celeron, overclock it to 120fsb and enable the 3:4 multiplier for my sdram. I would then have my ram at 160mhz cas2. This would be even better than running a 1.1a @ 145fsb. And you dont have to deal with the luck of buying a chip. Im pretty sure it is guaranteed to hit 120.

Otherwise my best bet would be a lower multiplier chip. a 1.1a or 1.2.

btw, i just bought a 1.1a but it wont even hit 124. Planning to get rid of it on ebay and try again.


thanks
 
OP
advanR

advanR

Member
Joined
Jun 11, 2002
I just remembered. I think it communicates inbetween the two. RAM and cpu.

It would be nice to see sandra memory scores for the two. A tualatin celly @ around 120 w/ 160mhz cas2 ram, and one at 145 fsb w/ cas2.

My estimate is that with sandra 2003 the one at 120mhz will get around 900 and the other will get 1050.

I'll check mine in a bit.
 

batboy

Senior Moment
Joined
Jan 12, 2001
Location
Kansas, USA
You didn't say want mobo you're using, but most socket 370 mobos do not allow you to "fix" the PCI and AGP bus, so that's probably why you have trouble being stable at high FSB speeds. If you can reach 133 FSB to enable the 1/4 divider, then your PCI bus will be back in spec. Most 1.1a CPUs will do 11X133=1463, if you have good cooling and maybe bump the voltage up a notch. Cooling is critical.
 

Maxvla

Senior Member
Joined
Jun 26, 2002
Location
OKC
fsb affects the entire computer not just the cpu and the memory.

and like batboy said if you don't have locks or good dividers you won't get very far.
 
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advanR

advanR

Member
Joined
Jun 11, 2002
Its not the mobo. I can run my 700E @ 135 all day long. It has 1/3 up to 120, and then 1/4 at 124 and above. The motherboard is an asus cuv4x. Im using an alpha pep66 for cooling. @ 1.7v it hovers around 35 degrees under load.

If you read my other thread I can set the voltage at 1.7 and it will still freeze while booting.

From what ive heard most 1.1a's will pretty easily hit 140-145 fsb.

Maxvla, what do you mean it affects the whole computer? Pls be more specific. In what way? I think i need to go read up to completely understand the fsb.
 

Maxvla

Senior Member
Joined
Jun 26, 2002
Location
OKC
advanR said:
Maxvla, what do you mean it affects the whole computer? Pls be more specific. In what way? I think i need to go read up to completely understand the fsb.
the FSB is the System Bus or the speed of the motherboard.

and since the motherboard affects everything the whole computer is affected.

when you change the FSB you change the PCI speed and the AGP speed which affects everything from your onboard accessories to your hard drive (which is on your pci bus)
 
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advanR

advanR

Member
Joined
Jun 11, 2002
yes, but by overclocking my pci bus and agp bus, i dont see how it would give me any higher scores in sandra tests. do you understand?

The only way it makes sense is to think of it as communicating in between the cpu and memory. Nothing else really matters for these tests.
 

Maxvla

Senior Member
Joined
Jun 26, 2002
Location
OKC
advanR said:
yes, but by overclocking my pci bus and agp bus, i dont see how it would give me any higher scores in sandra tests. do you understand?

The only way it makes sense is to think of it as communicating in between the cpu and memory. Nothing else really matters for these tests.
you are correct. o/cing the pci and agp bus will not get you anything. but it can hurt your performance or even impede your o/c progress so its important to know what you are doing.
 

batboy

Senior Moment
Joined
Jan 12, 2001
Location
Kansas, USA
Max is right on the money... overclocking your AGP and PCI (controller and harddrive) sure does help performance benchmarks (at least a little), but CPU clock speed and memory bus speed has the greatest effect.
 

Maxvla

Senior Member
Joined
Jun 26, 2002
Location
OKC
batboy said:
Max is right on the money... overclocking your AGP and PCI (controller and harddrive) sure does help performance benchmarks (at least a little), but CPU clock speed and memory bus speed has the greatest effect.
i said you get no gain. but thats not entirely correct. the gain that you MIGHT get is so insignificant i just completely disregard it.


i keep my pci/agp locked at 33/66 anyways :D
 
OP
advanR

advanR

Member
Joined
Jun 11, 2002
so in theory a 1.4 at 1680 with 160mhz cas 2 will be faster than a 1.1a at 1595 or 1.2 at 1596-1680? Im benchmarking my system in a minute so ill have the one end of it.
 

Maxvla

Senior Member
Joined
Jun 26, 2002
Location
OKC
umm. not sure what you are asking.

the higher the fsb the better the rest of the system will perform.

good measure is the 2.5a and 2.53b while stock the chips are nearly identical in speed the 2.53b will dominate the 2.5a by a significant margin in any test due to the fsb being 133mhz instead of 100mhz for the 2.5a.

does this help?
 
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advanR

advanR

Member
Joined
Jun 11, 2002
Im saying a 1.4g celeron with 120mhz fsb utilizing 3/4 for memory will be running memory at 160mhz. The fsb is considereably lower than the lower multiplier cellys, but because the memory is so much faster I was wondering if it would have an advantage. I was comparing this to a 1.1a or 1.2 at 145 or 133 respectively.

Do you understand? I was thinking a 1.4 at 1680 with 160mhz ram would be optimal. But maybe it isnt.

My sandra memory scores were 901 and 890. This is a lot less than expected because without the 3/4 i get 891 and 883.

Can someone compare this to their 133-145 fsb celly?
 

TUK101

Member
Joined
Jun 27, 2001
Location
Wash. State
Basically the higher the fsb, the less of a bottleneck when trying to get data from point A to point B. There is a reason that they are phasing out sdram, and it is because it is so bandwidth limited. DDR effectively gets twice the work done per clock cycle and in effect works at twice the fsb. It is also another reason that all of us OC'ers would love to see the multiplier unlocked on our Pentium chips. If we could change the multipler we could lower it, and raise the fsb which effectively amplifies the OC. You can also think of it like this.... would you rather mow your lawn with an 18 inch wide lawnmower, or a 24 inch wide lawnmower? Both mow lawn and have a 3.5 horsepower engine on them, but one is just 6 inches wider ad gets 1/3 more work done per pass. Kindof a strange analogy, but it gets the point accross. :eek:
 

Maxvla

Senior Member
Joined
Jun 26, 2002
Location
OKC
advanR said:
Im saying a 1.4g celeron with 120mhz fsb utilizing 3/4 for memory will be running memory at 160mhz. The fsb is considereably lower than the lower multiplier cellys, but because the memory is so much faster I was wondering if it would have an advantage. I was comparing this to a 1.1a or 1.2 at 145 or 133 respectively.

Do you understand? I was thinking a 1.4 at 1680 with 160mhz ram would be optimal. But maybe it isnt.

My sandra memory scores were 901 and 890. This is a lot less than expected because without the 3/4 i get 891 and 883.

Can someone compare this to their 133-145 fsb celly?
wow i haven't seen memory scores like that in a long time :eek:

basically you want a computer that is more even in its speed. you don't want a computer with a chip at 4ghz and the memory at 33mhz and likewise you don't want memory at 500mhz sitting next to a pentium pro 200mhz.

those are extreme examples but you get the idea. the ideal system is to have a good o/c on the chip and a good o/c on the memory and not have to sacrifice speed of one for the other.
 
OP
advanR

advanR

Member
Joined
Jun 11, 2002
ummmm i dont understand what your saying. I dont think we communicate too well, lol.

Im just trying to get the most for my money and have a faster sstem until febuary-march. then its a dual ddr p4 rig most likely.

But yes i want the best memory scores and atleast a 1500mhz cpu.

sooo........, if someone could post scores for a tualatin celly at 133-145 i would greatly appreciate it. I used sandra 2003.

thanks