Epox 8KDA3J volt mods

[bh2k]

These mods are for anyone who cares or needs them.

Vcore mod:
50k Pot at max resistance
Pin10 to ground
http://www.intersil.com/data/fn/fn9084.pdf



Vdimm:
Vdimm on this board is taken from the 5v line so no need to mod the 3.3 line on the psu. The vtt also tracks so no need to mod that.

10k post at max resistance
Pin6 to ground
http://www.richtek.com.tw/Product/Docs/DS9202-02.pdf



Read points:



Any questions post here.

[kleptophobiac]

How's vcore stability when using the mods?

My 8KDA3J+ has horrible voltage stability... I set the BIOS vcore to 1.55v and get 1.30. There's almost no relevance between what's in the BIOS and what's actually given to the CPU. If I leave the BIOS at a certain voltage and use the POT to change it, will the board be more likely to have the voltages stay put?

Or is there a modded BIOS with better voltage control?

[topcat]

Just did the VDimm mod and worked great! Thanks. Have my Mushkin blue UTT running 240mhz @ 3.15v 2-2-2-10 on 8kda3j. My new amd64 3000 CBEC 0421 tpmw will do 2500mhz but runs too hot with 1.65v, loads out at 60c. 1.55v 2400mhz is 38c idle and 52c load. My 3200 Clawhammer would only do 2200mhz so I bought a Newcastle on sale cheap and it rocks.My CPU voltage fluctuates also and this is the second revision with active cooling on the chipset. At least it fluctuates upward. Will go from 1.55 to 1.61 when set to 1.55v in bios.Any one have a stable board(VCore)?What power supply?I use an Antec PP412 with adjustment pots inside.Did the Vcore mod help?Thanks.

[Lithan]

You are linking to the 6559, the pic shows a 6569.

Also I just got a rev 2.2 which uses sc2643vx, which according to docs Im finding uses pin 7 instead of 10. If you can take a look and verify, that'd be great. http://www.semtech.com/pdf/sc2643vx.pdf&e=10053

[celemine1Gig]

You are linking to the 6559, the pic shows a 6569.

Also I just got a rev 2.2 which uses sc2643vx, which according to docs Im finding uses pin 7 instead of 10. If you can take a look and verify, that'd be great. http://www.semtech.com/pdf/sc2643vx.pdf&e=10053

Pin 7 "FB" looks OK to me. If I'm not mistaking, "OUTSEN" should also work, as they are both connected to the same Error Amplifier. So changing either one should work. Although I'd personally use the FB pin.

[1860ly]

is the 8KDA3I for the same mod~~??

[celemine1Gig]

is the 8KDA3I for the same mod~~??

Look at the chips then you'll know.

[boshi]

Sorry to dig up something so new, but is anyone certain as to the accuracy of the vtt and vdimm sense points there? I'm reading about .4v higher in bios than from that leg.

[celemine1Gig]

You can also measure in a empty Dimm-Slot, thus you measure what the RAMs are really getting. But I doubt it'll be different from what you are getting as a reading from the Mosfet legs. Don't ever take the BIOS readings for real. They'll never match what a good (or even a bad) DMM will throw out.

[boshi]

Interestingly I looked up the pinout on the DIMM slot and found somewhere to read from, and it agrees with the bios. I suggest this be a warning to anyone who trusts the mosfet, lest they kill their ram.

Also does anyone have a VTT mod for this board?

[celemine1Gig]

Interestingly I looked up the pinout on the DIMM slot and found somewhere to read from, and it agrees with the bios. I suggest this be a warning to anyone who trusts the mosfet, lest they kill their ram.

Also does anyone have a VTT mod for this board?

Hehe, really funny. Then the Epox-team must have done their job good. You see, there's always an exception to the rule. BTW, normally the mosfet reading should exactly be the same as the one on the dimm slot. Quite strange.

[Misko]

Could somebody thels me, where is the read point for vcore, and i notice that vcore is pretty unstable, when i run some benchmark, vcore go up about 0.05-0.07V and thats a lot.