Ok being a good OC newbie I decided to try 1007.002 the other night. So I started playing around with all the usual OC suspects and I came across a couple of things that I'd like to share.
I did all my testing exclusively with memtest86 booted from a CD so that if I had a "bad" OC config I wouldn't corrupt the boot sectors of my system.
1) My memory (2x512MB Corsair CMX512-3200C2PT) has a "magic number" for throughput of 2400MB/S. The closer I got to that the more likely I was to get a hang or complete failure to POST. Does this make sense?
2) The max memory setting AND the cpu multiplier work together. So to say that setting your max mem to 333 means a 5:6 (or 400 * 0.833) ratio based on 333/400 is a bit of an over simplification.
I believe the formula is actually
Round(CPU Multiplier / (Max Mem/400),0)
So for example
Mem Divider = 266
CPU Multiplier = 8
Effective Mem Divider = 12
FSB = 300
CPU Mhz = 2400
Mem Mhz = 200
A slightly more complicated example (my runtime settings):
Mem Divider = 266
CPU Multiplier = 8.5
Effective Mem Divider = 13
FSB = 306.5
CPU Mhz = 2605.4
Mem Mhz = 200.4
I created a matrix and checked a couple of these with CPU-z and I got the result I predicted. I'd appreciate any feedback.
NOTE: Save the following as a csv and then open in excel.
---START CSV---
,,,,CPU Multiplier ,,
Memory Divider,Ratio (Divider/400),9,8.5,8,7.5,7
500,1.25,7,7,6,6,6
433,1.0825,8,8,7,7,6
400,1,9,9,8,8,7
333,0.8325,11,10,10,9,8
266,0.665,14,13,12,11,11
200,0.5,18,17,16,15,14
---END CSV---
However I don't think that is the end to the memory throughput mystery. I dont quite have a handle on the formula for different memory latency settings.
John