Does FSB matter to a CPU?

[BZeto]

I'm wondering because I can do 2100 mhz easy using 195x11. But I cant run stable or most of the time even boot using 200x10 which is only 2000mhz. That extra 5mhz on the FSB causes all sorts of problems. Does the CPU even recognize the FSB it must run at, or just the overall clockspeed?

I'm asking because if clock speed is all that matters than I can be sure my CPU isn't the problem in attaining 200 fsb.

 

[Soulkeeper]

100mhz is much more important than 5mhz fsb increase
no contest imo

 

[oldman420]

i have found in my ocing adventures that fsb is less important than the multi in not only stability but performance as well.
i have tried 200 mhz x 11 vs 220 x 10 and found i get much more stability out of the former i also got better gaming results

 

[AnnoyedGrunt]

I don't think he's asking which one is better necessarily, but why is that small jump causing problems.

Your CPU shouldn't really care what the FSB (unless it is multiplier locked, but it sounds like yours isn't). However, all your other components will care, so unless you have a PCI/AGP lock, it could be possible that you are pushing something else too hard.

Could it be your RAM? Your sig says PC2700 and I see you have a pretty old setup, so increases in FSB will probably bump up HDD, video, etc. PC2700 is rated @ 166 I think, so maybe that's why you can't hit 200?

I'm not much of an overclocker, so I'm just kinda spouting what I've read on this site. You may just want to ignore me

-D'oh!

 

[BZeto]

Thank you for the replies. I am trying to reach 200fsb. If I can get there, I'll be happy. But I cant get there, even though all my parts are rated/should do 200 fsb without a hitch.
Abit NF7-S (200fsb is within its factory rated specs, correct?)
AMD Mobile 2500+ (judging from what everyone with a mobile says, this should do 200fsb EASILY)
Corsair XMS PC3200 (this stick is tested to run at 217fsb stable)

I know my RAM is good, that leaves me with the motherboard and CPU. It cant be my CPU because like I mentioned it runs fine at 2.1Ghz (using 195fsbx11), so therefore it should be able to do 2Ghz (using 200fsbx10). Unless for some reason the CPU really does 'stop' at a certain FSB.

So I am inclined to beleive it is my motherboard that is faulty.


EDIT: Sorry I forgot to mention my specs, since the system in my sig what I am upgrading from.

Its the same in my sig except I am now using:
Abit NF7-S
AMD XP Mobile 2500+
512mb Corsair XMS PC3200

 

[DKlein]

You could try underclocking your CPU, raising your RAM timings and running it asynch, and then upping the FSB to 200 to be sure if it's the motherboard. I've heard some have had problems even hitting 200. Do you know what revision it is?

 

[DAPUNISHER]

Bump the ram voltage a bit, then if needed bump the vdd chipset voltage a notch too. I also suggest setting the system to expert and making the ram speed 100%.

 

[BZeto]

Originally posted by: DKlein
You could try underclocking your CPU, raising your RAM timings and running it asynch, and then upping the FSB to 200 to be sure if it's the motherboard. I've heard some have had problems even hitting 200. Do you know what revision it is?

How exactly would I do this? I'm sorry but I dont know what you mean by running it asynch.
My board is a Rev2.

 

[Shimmishim]

Originally posted by: oldman420
i have found in my ocing adventures that fsb is less important than the multi in not only stability but performance as well.
i have tried 200 mhz x 11 vs 220 x 10 and found i get much more stability out of the former i also got better gaming results

that's interesting because i when i had my A64

i got better results with 9 x 289 than i did with 10 x 260

fsb > clockspeed especially on the p4's.

right now i'm running 14 x 207 on my system but onc ei test out a second cpu, i'm going to max out my fsb...

 

[DAPUNISHER]

Originally posted by: Shimmishim

Originally posted by: oldman420
i have found in my ocing adventures that fsb is less important than the multi in not only stability but performance as well.
i have tried 200 mhz x 11 vs 220 x 10 and found i get much more stability out of the former i also got better gaming results

that's interesting because i when i had my A64

i got better results with 9 x 289 than i did with 10 x 260

fsb > clockspeed especially on the p4's.

right now i'm running 14 x 207 on my system but onc ei test out a second cpu, i'm going to max out my fsb...

I'll tell ya Shim, there's a lot of the old Mantras still running around that are FUD given the performance evaluations of current hardware. Just replied to a thread where someone was ranting that tight timings were the absolute must and sooo important for a new AMD64 system :roll: Still see the "Oh Nooooooes!!!!1!!! my CPU load temp is 55c" posts too. Let's not forget the "stock thermal pad is crap! use ASS5" I just read. Nevermind that they didn't research the product and discover it's a high quality Shin-etsu T.I.M. People don't read enough of what is being tested and reported by reviewers and forum members anymore I guess=

 

[DKlein]

Originally posted by: BZeto

Originally posted by: DKlein
You could try underclocking your CPU, raising your RAM timings and running it asynch, and then upping the FSB to 200 to be sure if it's the motherboard. I've heard some have had problems even hitting 200. Do you know what revision it is?

How exactly would I do this? I'm sorry but I dont know what you mean by running it asynch.
My board is a Rev2.

To run your RAM asynch, go to your BIOS and I believe it is the first option (can't recall name offhand - general properties maybe). It's the same screen that you set your processor speed I think. There will be an option somewhere in there for RAM:CPU ratio. A 1:1 ratio would mean that the RAM FSB is = CPU FSB, a 2:1 would mean that RAM FSB = 2x CPU FSB. Drop it down below 1:1 to something like 5:6 or perhaps lower. Now your RAM will run a much lower FSB than the chipset.

To underclock the CPU just lower the clock multiplier by enough that the CPU will not be running faster than stock. Then up the freq until you start seeing problems, this is the FSB limit of the motherboard. Then you can lower it a bit from there and see if the RAM works 1:1 (in synch) with that, if not start over and see how high the RAM will go. Then you just up the clock multiplier and see how high the CPU will go. Of course you can up the voltages as well while doing this all to get the max speed. BTW what would you guys consider the max safe voltage for the chipset and RAM on that setup? I know for that processor, 1.8V is about it.