- Joined
- Aug 27, 2003
- Location
- Mississauga, Ontario
I just have a couple quick questions.
Firstly, is it wise to go above 1000 hypertransport? The rig in questions is the s939 in the sig, and I'm wondering whether it's better to keep the HHT under 1000 at all costs or not.
For example, right now I don't need too much overclock, so I'm running at 250x4 for exactly 1000 (instead of 200x5 default), this is still a significant overclock over the stock Opteron 165, but the CPU can handle much more, I've had it over 2.5GHz stable no problem.
Now, if I want to run 260fsb, can I keep the HHT multi at x4 or is that going to cause problems? So first question is, is there any point in going over 1000, and how low can I go without it causing ANY slowing of the system.
I always thought that the hypertransport is way above what the system needs, so if I ran my 250x4 (as I do now) at 250x3 instead, for 750 instead of 1000, there would be no difference at all, since there is still much overhead, and in reality all the HHT needs to do is run at 400MHz to allow full throttle (unless memory is overclocked over 400MHz of course). Am I right on this, and if not, what is the lowest HHT that I should go to.
I'd like to run something like 280x8.5, but I fear that is way too high for x4 multi on the HHT, there is no 3.5, so I'm stuck with 3x which well under 1000, 840 in fact. So, what is the lowest?
This brings me to the secondly. Is there an exact formula for CPU to memory multiplier. It's incredible how crazy the memory MHz numbers get when I change the multiplyer. If I keep it at it's highest 9x, then it's just a matter of CPU/11, but as soon as I change the multiplyer, everything goes haywire, for example if I run 300x8 for 2.4GHz, the usual formula which works with 9x multi doesn't work and the memory is trying to run at over 300MHz (600Mhz DDR), craziness. One time I tried 320x7.5 and when I put the memory multi to it's lowest (1/2, 100MHz), it ran at over double it's rated capacity (almost 400MHz/800MHz and failed immediately), and funnily enough, when I put the divider on the memory higher, the frequency went lower, and changing the cpu multiplyer changes it all again. It is only clear to me when I keep the multiplyer at 9x, but that doesn't allow me to achieve my full O/C potential, unless of course my first inquiry here is correct and HHT really doesn't matter and can be run as low as 750MHz without any loss of performance (750MHz is a number I'll never run that low, it's just an example from above, but I would like to run 280x3 for example for HHT, and a 8.5 multiplyer, but again, that screwes with the memory and I have to test every setting and even then I have no guarantees, I need a formula if there is one. I am an advanced computer user, builder, repairer, overclocker etc, but this is eluding me, but I am an astrophysicist, so any formula will be a big help no matter the complexity.
So, is there a formula that takes into account FSB and the multiplyer of the CPU and the memory divider together on the Ultra-D s939 motherboard?
Thank you.
Firstly, is it wise to go above 1000 hypertransport? The rig in questions is the s939 in the sig, and I'm wondering whether it's better to keep the HHT under 1000 at all costs or not.
For example, right now I don't need too much overclock, so I'm running at 250x4 for exactly 1000 (instead of 200x5 default), this is still a significant overclock over the stock Opteron 165, but the CPU can handle much more, I've had it over 2.5GHz stable no problem.
Now, if I want to run 260fsb, can I keep the HHT multi at x4 or is that going to cause problems? So first question is, is there any point in going over 1000, and how low can I go without it causing ANY slowing of the system.
I always thought that the hypertransport is way above what the system needs, so if I ran my 250x4 (as I do now) at 250x3 instead, for 750 instead of 1000, there would be no difference at all, since there is still much overhead, and in reality all the HHT needs to do is run at 400MHz to allow full throttle (unless memory is overclocked over 400MHz of course). Am I right on this, and if not, what is the lowest HHT that I should go to.
I'd like to run something like 280x8.5, but I fear that is way too high for x4 multi on the HHT, there is no 3.5, so I'm stuck with 3x which well under 1000, 840 in fact. So, what is the lowest?
This brings me to the secondly. Is there an exact formula for CPU to memory multiplier. It's incredible how crazy the memory MHz numbers get when I change the multiplyer. If I keep it at it's highest 9x, then it's just a matter of CPU/11, but as soon as I change the multiplyer, everything goes haywire, for example if I run 300x8 for 2.4GHz, the usual formula which works with 9x multi doesn't work and the memory is trying to run at over 300MHz (600Mhz DDR), craziness. One time I tried 320x7.5 and when I put the memory multi to it's lowest (1/2, 100MHz), it ran at over double it's rated capacity (almost 400MHz/800MHz and failed immediately), and funnily enough, when I put the divider on the memory higher, the frequency went lower, and changing the cpu multiplyer changes it all again. It is only clear to me when I keep the multiplyer at 9x, but that doesn't allow me to achieve my full O/C potential, unless of course my first inquiry here is correct and HHT really doesn't matter and can be run as low as 750MHz without any loss of performance (750MHz is a number I'll never run that low, it's just an example from above, but I would like to run 280x3 for example for HHT, and a 8.5 multiplyer, but again, that screwes with the memory and I have to test every setting and even then I have no guarantees, I need a formula if there is one. I am an advanced computer user, builder, repairer, overclocker etc, but this is eluding me, but I am an astrophysicist, so any formula will be a big help no matter the complexity.
So, is there a formula that takes into account FSB and the multiplyer of the CPU and the memory divider together on the Ultra-D s939 motherboard?
Thank you.