8rda+ rev 2.1 Vcore problem

[tomiapk]

I have a problem with Vcore voltage rise. I just cant get it above 1.850. Computer simply doesnt restart.

Epox support sayd the problem must be in CPU...

What do you guys think????

Regards!!!

-Tomi-

CPU xp2500+ barton
ep-8rda+ rev.2.1
256mb pc3500 corsair 2cl
300W Q-TEC

Everything cooled

[Holst]

Its a problem with the changed vreg.

I never found a satisfactory fix for this issue.
I did work out a volt mod but stability was severly compromised, and I changed to an 8rda3g rather than mess around any further.

[ryssen]

I have the same problem.

[jonspd]

http://www.motherboardfaqs.com/article.php?31.255

[ryssen]

I have Rev 2.1 and the chip is CS 5301, anyone know if its the same layout as Rev 1,0

[Holst]

its totaly different.

Same as 8kha+, although 8kha+ mods dont work.

I have managed to get upto 2.2v from a rev 2 but im not posting the mod as it was far from stable.
I also removed the OCP using the same method as macci did on his 8kha+ ... with no gains.

I no longer have one of these boards for further testing, ill be impressed if anybody can get a working mod for this board.

[ryssen]

Can you please post the mod as I have nothing to start from, maybe I can get it stable.Or you can e-mail it to me.

[Holst]

What I did was alter the VFB state, but it was highly unstable and totaly pointless... and you wont get a working mod that way either.

I think the best way will be to ift the FB pin from the board and set your own resistor deviders.

Might also help to lift the VID pins to force 1.85v before you start as well.

[ryssen]

Do yoy have a pin layout on CS 5301?

[Holst]

http://www.onsemi.com/pub/Collateral/CS5301-D.PDF

[YoupY]

I've read parts of it and pin 2, 3 en 32 are interesting

Pin 2:
Voltage Feedback Pin. To use Adaptive Voltage Positioning
(AVP) select an offset voltage at light load and connect a
resistor between VFB and VOUT. The input bias current of the
VFB pin and the resistor value determine output voltage offset
for zero output current. Short VFB to VOUT for no AVP.

Pin 3:
Current sense output for AVP. The offset of this pin above the
DAC voltage is proportional to the output current. Connect a
resistor from this pin to VFB to set amount AVP or leave this
pin open for no AVP.

Pin 32:
A resistor from this pin to ground sets operating frequency
and VFB bias current.

[The Doctor]

Originally posted by Holst
its totaly different.

Same as 8kha+, although 8kha+ mods dont work.

I have managed to get upto 2.2v from a rev 2 but im not posting the mod as it was far from stable.
I also removed the OCP using the same method as macci did on his 8kha+ ... with no gains.

I no longer have one of these boards for further testing, ill be impressed if anybody can get a working mod for this board.

Could you post or e-mail me a description of the mod im very interested in it.

Mail: vnrswk@(NOSPAM)Kabelfoon.nl

[Holst]

As ive allready stated it dosent work, and I am not releasing it.. as it dosent work...

Im not saying a mod cant be done and I can start helping you guys carry on... but my previous experiments were totaly in the wrong area.

I think the best way will be to do as I posted above, lift the pins and set things up manually.

[ryssen]

I think the best way will be to ift the FB pin from the board and set your own resistor deviders.

If I use a VR how should I connect it?

[Holst]

Its a bit more complex than that, you would need to read the PDF and work out how to manually set up the Vreg, then lift allot of the pins and rewire it.

There may be other solutions but I didnt find one...

As I no longer have a board to mess with its difficult for me to help further.. and I dont want to be advising you to take potentially lethal and untested mods if you dont fully understand them.

Sorry I cant help further...

[ryssen]

Anyone tried this on a 8RDA+ V2.1?
http://www.aoaforums.com/forum/showt...oto=nextoldest

[Holst]

I also removed the OCP using the same method as macci did on his 8kha+ ... with no gains.

Yep, I tired it. didnt work.