FSB, cas latency, and overclocking with Corsair PC133 RAM..

[PlunX]

I just got my stick of Corsair PC133 RAM today and I'm not quite sure which settings to use in the BIOS for it.. I've heard some people setting their PC133 RAM to 100MHz, is this a good idea? What's the point of this? Also, should this RAM make my overclocking-through-FSB better?

 

[whalen]

Are you using this for your duron system? If so, setting the memory to 100 wont make any diff because you cant really overclock the kt chipsets well via fsb

 

[GaryTcs]

The only reason to set your PC 133 to Pc 100 is for failure to boot-up properly. If you FSB oc your duron to 107 mhz, pc100 is running at 107mhz, and pc133 is running at 142mhz. If you take it up to 113, pc100 is only at 113mhz, whilr pc133 is at 150. Some pc133 cannot do 150, even at cas3. This is when you would set your ram speed down. Remember though, sometimes this is not worth the trade off for a higher processor clock speed. You lose more in memory than you gain in CPU mhz.

 

[PlunX]

Well, I have the RAM speed set to 133MHz at cas2 and the FSB at 112MHz (112*9.0=1.008GHz) and I'm not having any problems.. Is that good, or is there a possibility that I could go higher if I set the RAM speed to 100MHz?

 

[GaryTcs]

That's pretty damn good for a Duron 600. You can keep trying higher bus speeds, but the processor likely won't let you get much farther. the highest I've had mine is 120, unstable, and pc 100 setting. Realistically though, 117 * 8.5 would be better if you can achieve it. Your ram would have to be outstanding to get this at pc 133 (155), and cas 2.

 

[PlunX]

Hrmm.. Seems the highest it can go is 113MHz. I'm running it right now at 113*9.0, getting around 1.02GHz. That's still as good as anything, right?

 

[GaryTcs]

Yeah, that's good. does this help? The CPU bus is at 2x multiplier. pc100 is = to multiplier, and pc133 is 1.33x multiplier.

Are you using sisoft Sandrato benchmark it? If not, download it and check those against the benchmarks provided with sandra.

Not many people get much more than 1ghz without modifying their motherboard and active cooling.

You should be satisfied with 1.02ghz.

 

[PlunX]

Well, here are my scores..

CPU Benchmark:
Dhrystone ALU 2834 MIPS
Whetstone FPU 1391 MFLOPS

CPU Multi-Media Benchmark:
Integer MMX Enh 5644 it/s
Floating-Point 3DNow! Enh 6867 it/s

Memory Benchmark:
Int ALU/RAM Bandwidth 437 MB/s
Float FPU/RAM Bandwidth 483 MB/s

Do these look alright or does it look like I'm being held back by something?

 

[GaryTcs]

Those scores look great to me. Above the Athlon 1ghz in almost every instance, and thrashing the 1ghz P3. not too shabby for a $50 processor, huh?