890FXE 4th core unlock strangenes

[Niku-Sama]

so ok, using a biostar 890FXE and finally getting arround to OC it, i was hoping to go past 3.45Ghz on a 720 BE with the 4th core unlocked. the reason? well on a biostar 790GX XE (a mATX board) i was able to run 3.45Ghz on all 4 cores. ram timings were holding me back (werent enough of them) and i wanted DDR3.

so here i am, off to start and i up the FSB and my 4th core goes away. just poof, acc is still on, core leveling only shows 3 cores now too. drop it back to 200 and it comes back, 201, it goes away.
same processor so i know its not the processors doing and i know it can do atleast 3.45 on all 4 from the other board

so what the heck? any ideas?
newest bios (from OCT '10) even

any way i am at 3.5Ghz (250 x 14 @1.404V) on 3 cores

 

[deadlysyn]

Have you tried working on the core offsets in the ACC menu at all (if available on that board)? Maybe a voltage issue?

Aside from that, I can't really be too much help, since the last thing I OC'd from AMD was my old XP3000+.

 

[QuietIce]

...

 

[RGone]

The 790X board was DDR2 and the 890X board is DDR3. The 3 core 720 cpu maybe a 3 core 720 cpu because one of the cores has an issue with the DDR3 mem controller within the cpu. Just because the fourth core worked on one type of motherboard is not anything like full assurance the fourth core will work on another type chipset motherboard.

You might have better success adjusting the core offsets in ACC if possible. Even that is not a guarantee of 4 core success.

 

[Niku-Sama]

well i find it strange that at stock FSB its working no problem but one Mhz over 200 it shuts off. DDR3 controller and all it seems to work.

in the ACC settings there isnt a way to get to the 4th core while its 201 or higher, or are you guys talking about adjusting the 4th one while its at stock FSB?

 

[RGone]

in the ACC settings there isnt a way to get to the 4th core while its 201 or higher, or are you guys talking about adjusting the 4th one while its at stock FSB?

Well then certainly try making the ACC setting while at default speeds.

 

[Niku-Sama]

no use on the ACC, i havent tried the multiplier only method yet. i was trying to get it to run stable at 3.5Ghz on 3 cores and it turns out i had too juch voltage going to the NB.

one thing i have learned about biostar boards...not all their stuff in the bios is labled correctly or working. adjusting NB VID in P states does NOTHING, i have to use the boards control of 0.0100v increases instead....and they arent all 0.0100v either