Setting FSB above 250 changes DRAM to 5:4---Why???

Question

Board is a MSI 865PE Neo2 PFISR
I can boot nicely with a 2.4C at 250 FSB at Synch 1:1
Move it 1 mghtz up to anything above 250 FSB----and it instantly clocks the RAM Asynch 5:4
Nothing I do in the bios will put me back at 1:1 even though my RAM is rated at PC4000 at 2.5, 7,4,4.
The bios (3.6)seem pretty flakey as well.
Different settings popping up after reboot----I have to constantly go in and reset things----recovering from an overclocking crash is a tedious process----many reboots involved before the settings seem to hold.
Suggestions???

Answer 1

Interesting thing to observed johnrr6, to be honest I'll never try the DDR500 as yours so I not trying this yet. In your case the bios could automaticaly change the DRAM Frequency when passing 275 mhz using DDR550 or PC4400.
The funny thing is my mobo should automatically set my DRAM Frequency as yours to ratio 5:4 when it passing the 217 mHz, but it doesn't do that which is same as AI7 nothing change the DRAM Freq.
Its good idea to find out the use of CC on OC Menu, it possible you have problem using DDR533 since its supposed to be DDR500, please let me know.
In my opinion you already have a great 250 mHz with your DDR500, and I dont thing it can do DDR533 setting but may be more a bit from 250 mHz with ratio 1:1.
Casing Tt Xaser III Skull
M/B 865 PE Neo-2 PFS Platinum Edition Bios Ver.3.6
CPU:P4 2.4C (HT enable) and ThermalTake SubZero 4G
(DOT Rank=Commander,Turbo,2395 mHz - 2760 mHz)
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