Asrock 939Dual-SATA2 Vmods

[persivore]

These are some of the existing mods for the board:
Vcore 1
Vcore 2
Vdimm

These a few new mods which I've found, which should release some better clocks from the board:

Vdroop - remove the circled resistor, and replace it with a 10k variable resistor set to 1k. Adjust until there is no droop.
Vsb - Southbridge voltage supply
Vtt - The board can produce a very unstable Vtt supply under some conditions. It should be 50% of Vdimm. Offsetting it slightly high or low can help to correct for the unstable voltage, and could improve RAM clocks slightly.
Vldt - Htt voltage supply - should help with Htt and possibly CPU overclocking.
Vdd - Northbridge voltage supply - Increasing Vdd should help with Htt overclocks.
Vagp - Might help increase the speed that the AGP bus can run at and might increase the Htt overclock, as on some intel based boards. I don't think that it will have much effect on this board tho personally.
Vpci-e - Same as Vagp

Vdroop
Vsb, Vtt and Vsb read point
Vldt, Vdd and Vagp mods
Vldt and Vdd read points
Vagp read point
Vpci-e and Vtt read point
Vcore read point

These are a couple of mods which I haven't fully tested yet, and should be done with caution until I have chance to fully test them. I think that the one in yellow is probably Vcca (PLL supply voltage for the CPU). I have no idea what the other mod controls, and doesn't seem to effect the overclock in any way.

Note: XS owners and members will not be liable for any damage caused to you or your hardware, neither can be liable for any breach of the warranty.

[crodan85]

Thanks persivore I will be trying the Vdroop mod tomorrow. Need to go too maplins

Just out of curiosity do you think changing the capacitors out for better quality ones would show any improvement

[persivore]

Thanks persivore I will be trying the Vdroop mod tomorrow. Need to go too maplins

Just out of curiosity do you think changing the capacitors out for better quality ones would show any improvement

I think the capacitors used on the board are already reasonably good quality. They're the same as the ones used on other Asus boards AFAIK.

[pancake]

nice work persivore, think ill try the vdroop , vldt and vdd mods

is the vtt mod needed with a ocz ddr booster?

[persivore]

nice work persivore, think ill try the vdroop , vldt and vdd mods

is the vtt mod needed with a ocz ddr booster?

Vtt tracks Vdimm fine on the board, but can sometimes be very unstable. Offsetting Vtt slightly might gain a few Mhz from the RAM.

[jonspd]

Any other mod's found or working with>?

how are the one's you tried coming along?

[persivore]

Any other mod's found or working with>?

how are the one's you tried coming along?

I've got some different Vcore and Vdimm mods for the board, but they are based on some of the existing mods. I'm also thinking of doing something to try to fix the Vtt fluctuations on the board.

I've managed to get this board up to 374mhz Htt with the mods. I'm not sure how much they have helped tho, because I wasn't running very high voltages at the time. The board feels like it is more limited by software/BIOS than voltage

[kyosen]

I uploaded my recent work for ASRock 939SLI23-eSATA2.

This board has similar Vcore circuit as 939Dual-SATA2,
but the method linked as "Vcore 1" by persivore doesn't work

I also tried Vdimm&Vhtt(Vldt) mod, but can't run over 260MHz memory clock
So I quited playing with this board...

[thegeek]

Wow, nice work persivore
I've already done vcore1 and I'm thinking about doing vldt and vdd to see if I can get some higher clocks from my opteron 165. I do agree that the board is probably limited by bad code. It is however an ok board considering the price

[Marvin_The_Martian]

Great work persivore.. this thread is subscribed!

[Marvin_The_Martian]

Persivore... damn that bios you linked me works like a charm

Guess my chip is a dud though can't get is stable at 2.7ghz, hard locks on spi32m on loop 2 all the time. Now running it @ 2.67ghz no problems yet!

Bios does have issues with booting after changing settings, have to turn off the pc and wait a while before I can boot it up. Also love the extra ram options!

Also I notice that my vcore is going up and down allot, from 1.57 to 1.60 up and down. That's bad aint it? Been doing this since the ocwbeta vcore mod but I installed a new psu at the same time so idk could be psu overvolting right? Anyone else any thoughts on this?

Edit: Also notice that cpu load during pi run sometimes drops back to 80%, mostly between loops ( eg when a loop has just finished ) does this mean it's throttling? Load temps are 32c so don't think so but seems odd

[Johnny Bravo]

Fantastic Persivore, and just in time as I've just purchased one of these. Would it be giving too much away if I was to ask you what you've set a few of the values to for instance, Vsb, Vldt and Vdd. Cheers mate, I look forward to experiemntating with this board and the OCWB beta bioses for it

[jonspd]

The german bios are better then OCWB bios.

found here http://www.pc-treiber.net/download-file-255.html

is you dont get it right you may get a file mismatch or wrong size error is so I have uploaded them and will post a link if wanted.

my link http://bellsouthpwp.net/d/c/dcracer/FAH/04XX.BIN


Just make sure the file size is 262,144 where ever you get it form and you should be ok.

[Johnny Bravo]

The german bios are better then OCWB bios.

found here http://www.pc-treiber.net/download-file-255.html

is you dont get it right you may get a file mismatch or wrong size error is so I have uploaded them and will post a link if wanted.

my link http://bellsouthpwp.net/d/c/dcracer/FAH/04XX.BIN


Just make sure the file size is 262,144 where ever you get it form and you should be ok.

What advantages does this bios bring to the table Jonspd?

[jonspd]

Cant really say much other then no cold boot issue for me from 274 to 300fsb unlike the OCW bios that dont boot sometimes after new setting's.

This was the 5th or 6th bios I tried and I have to say it was the keeper out of them all. If you havn't tried them I really cant tell you much other then they are awesome.

only result's I can say people posted about them
http://www.ocforums.com/showthread.php?t=443563

[Johnny Bravo]

Cheers mate

[persivore]

Fantastic Persivore, and just in time as I've just purchased one of these. Would it be giving too much away if I was to ask you what you've set a few of the values to for instance, Vsb, Vldt and Vdd. Cheers mate, I look forward to experiemntating with this board and the OCWB beta bioses for it

I'm running 1.9v Vsb, 1.4v Vldt and 2.15v Vdd. I've managed to get the board up to 379 Htt with those voltages, using the 04XX bios. It seems stable at 350 Htt with a Htt multiplier of 3

[jonspd]

Nice I havn't gone above 2.08 vdd and still yet to do vcore mod

[Johnny Bravo]

I'm running 1.9v Vsb, 1.4v Vldt and 2.15v Vdd. I've managed to get the board up to 379 Htt with those voltages, using the 04XX bios. It seems stable at 350 Htt with a Htt multiplier of 3

Cheers persivore, board arrived this moring and I've an Opty 146 in the post, although reading around on the Rebels Haven it seems Venice cores are the cpus of choice for this board, should be interesting tho for the time being. I'll get some details up as soon as the processor arrives.

[littleowl]

Ok I guess I am not smart enough to get this!! why do it and what would I get out of doing all that work!?

[littleowl]

Great work and nice info, only If I understood why to do it though!

[Johnny Bravo]

ummm to improve maximum overclocks...simple as that

[thegeek]

Would be nice if someone could post the default volts for all the mods.

[Marvin_The_Martian]

Think you can measure those before modding

[persivore]

Would be nice if someone could post the default volts for all the mods.

Defaults:
Vdd (northbridge) - 2.0v
Vsb - 1.8v
Vldt - 1.2v
Vagp - 1.5v
Vpci-e - 1.8v
Vcca - 2.5v