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FSB v. Timings question

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gmas

Registered
Joined
Jul 24, 2003
Location
NJ
I understand that all results are relative, and the only true answer would come through benchmarking my own setup, but I'm looking for a general consensus for a couple of questions.

At what gain in FSB would it be worth relaxing the memory timings?

At what gain in total overclock would it be worth dropping the FSB?
 
Well what you said is right!
We can't tell you the exact point where you shold to bla bla..

What I can do is answer generally.
1) That's up to your ram, and mobo. also, if you are running an Intel system or using a locked barton and you need/want more MHZs you should drop the timings a little and get more fsb/mhz.
2) Well, if you see that for example 220x10.5 (2310MHz) with 2-2-2-5 is better then 230x10 (2300MHz) with 2.5-4-4-8 you should drop your fsb IMHO.

Hope I helped, sry for the lame English.
Suma.
 
No problem on your English my friend, I understand you just fine. And, I appreciate your response.

I'm certainly not looking for an exact point of diminishing return, or any definitive answer for that matter. I'm merely looking for opinion, based on experiences.

For example: do you think it's worth an increase of 2-3fsb, if you have to relax your timings from 2-2-2-6 to 2-3-3-7?

BTW, I'm currently running two setups:

NF7-S v2.0 213FSB
Barton 2500+ (unlocked)
Corsair XMS3200 2x512 @2-2-2-11(Dual)

NF7-S v2.0 200FSB
XP1700+
Corsair XMS3200 1x512 @2-2-2-11

Thanks for any input!
 
No, it is not worth the 2/3 FSB and relaxing the timing from 2-2-2-11 to 2-3-3-11, the performance is still better using the slower FSB and very tight timing.

From my experience, you need at least 20 FSB to compensate the timing relaxation from 2-2-2-11 to 2-3-3-11.
 
hario said:
No, it is not worth the 2/3 FSB and relaxing the timing from 2-2-2-11 to 2-3-3-11, the performance is still better using the slower FSB and very tight timing.

From my experience, you need at least 20 FSB to compensate the timing relaxation from 2-2-2-11 to 2-3-3-11.

Thanks for the reply!
 
I think that's generally true when the CPU mhz stays the same. ie. The increase in fsb is the only thing that's offsetting the lower timings. However, as I think Suma was touching upon, it's different if you have a locked Barton, which it seems like you do.

An increase in cpu speed will be far more noticeable than an increase in fsb or a lowering of memory timings. Like in Intel systems (where's it always multiplier locked), raising the fsb as high as possible is pretty much always good.

Edit: Errr, n/m. For some reason, I read your post as saying you had a LOCKED barton. Clearly, I was mistaken. So yah, in that case, I agree that raising fsb by raising timings is pretty much only worth it when you can do it in the ballpark of 20mhz. However, don't forget if your cpu mhz goes up too (which can happen. IE. You can do 200x11 but not 200x11.5. So you want something in between. Multi won't do it, so you increase fsb to like 205x11, 55 more cpu mhz. CPU mhz is worth much more than fsb mhz or raising timings a little.
 
Yes, obviously 205x11 will give me more performance than 200x11. The question is will 205x11 give me more performance than 200x11.5?

In other words, will the 5mhz increase in fsb more than compensate for the loss of 45mhz in CPU speed, due to the fact that the fsb bump affects the total system throughput, as opposed to just a gain in CPU speed?
 
gmas said:
Yes, obviously 205x11 will give me more performance than 200x11. The question is will 205x11 give me more performance than 200x11.5?

In other words, will the 5mhz increase in fsb more than compensate for the loss of 45mhz in CPU speed, due to the fact that the fsb bump affects the total system throughput, as opposed to just a gain in CPU speed?


wonderful question i ahd the same in mind
im hoping someone can answer it well
 
I think you may have somewhat misinterpreted what I was trying to say there. It wasn't that 205x11 is better than 200x11 (because that's obvious). But that CPU speed is more important than Memory timings. So like, 210x11 @ 2-3-3 is better than 200x11 @ 2-2-2, not because the fsb is higher, but because your cpu speed would be considerably higher. FSB/mem timings are not the end-all or be-all of performance, CPU matters much more.


So with something that small (205x11 vs 200x11.5), I would say no, the 200x11.5 would be much better.
 
tyson-chris said:
I think you may have somewhat misinterpreted what I was trying to say there. It wasn't that 205x11 is better than 200x11 (because that's obvious). But that CPU speed is more important than Memory timings. So like, 210x11 @ 2-3-3 is better than 200x11 @ 2-2-2, not because the fsb is higher, but because your cpu speed would be considerably higher. FSB/mem timings are not the end-all or be-all of performance, CPU matters much more.


So with something that small (205x11 vs 200x11.5), I would say no, the 200x11.5 would be much better.

Thank you for clearing that up, I did misinterpret your previous reply.
 
This thread is gold. Thank you gmas for asking such a fine question and you, tyson, for providing the answer.

-SynapticBliss
 
It's even more tricky when running an Intel rig where you can't always run 1:1 speeds. Do you choose a "slower" speed (like 5:4 or even 3:2) with tighter timings, or a "faster" speed (1:1) at loose timings?

Actually the answer is, I dunno :p I personally like running 1:1 at severe speeds because it just gives you that manly computer-nerdy aura ;) :p In reality, the performance is likely pretty similar.

I believe the general consensus is that AMD's perform better with tighter timings, whereas Intel's usually don't suffer as much from the loose timings.
 
And the plot thickens!!

I'm still looking for more input. Any opposing points of view?
 
I would go for a combination for high fsb, low timings, and nice mhz. I get 20k with my rig on the signature whereas others on a board with a lower fsb would have to increase mhz to 2.5-2.6+ to achieve the same result. I get 3750 in Sandra @ 97% efficiency (at work so no shots). If I increase my o/c to 2.5, I get 21k. OCZ has some bh-6 that runs 2-2-2-7 on 2.7v and can get up to 250 fsb. Ram like that with an unlocked or mobile barton can be your best friend. Basically what I'm saying is that you should prefer high fsb @ the lowest timings possible, especially over raw mhz.
 
Well it makes since if u think about it....Lower FSB and Tighter Timmings are great...Higher FSB and looser timmings are great also...it all equals out...personally i would go with the second choice...
 
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