Like 8Pack said there's a some connection between the 0.95V rail (also seen referred to as reference voltage) & Core Voltage.
Why exactly, can only be explained by an Engineer with Knowledge of the PCB. The Stilt probably knows it, dunno if he'll explain it or not.
As far as I'm concerned he hasn't. I asked him the question about my blackscreens but no answer like yours...
I believe he knows how to chage it easily and maybe he could even tell us if its possible to do it in bios.
Well I decided to do the opposite of what I was gonna do.
I took the bios from KingPin forum and only changed VoltageObjectInfo table. The table in the Matrix ROM is the shortest I've seen, so far. This has helped identify fully the segment responsible for UP6266 in (VoltageObjectInfo/VRAM_GPIO_DetectionInfo). Compare(Click to show)
Note no ROG logo between Tuning & LiveUpdate buttons on left vertical side plus semi transparent black skin to app.
Next results of using Matrix_ln2-elpida ROM (it has Hynix AFR support as well).
As you can see GPU Tweak has detected Asus card, but no Matrix features. To me it would seem this 0.95V rail / VRM switching tweak feature is proprietary to Matrix, due to custom PCB.
Will spend bit of time dissecting bios but don't think it will yield anything.
The register 8F in Matrix VoltageObjectInfo I will research, first time seen one like that there. There was really only that register to set up IR3567B, data value 01; so the rest of programming for IR3567B would be MTP.
If I view my i2cdump (with my own ROM) register 8F has data value 1F (not set by ROM but MTP), again as I have custom PCB (12 phase) didn't wanna risk my card testing change.
My pastebin has tables for the Matrix ROMs if another wanna check ROMs as well. Will still try to gain an i2cdump from a Matrix owner to see what controllers on that card.
*** edit ***
Made contact with an owner of Matrix CF setup on HUKD, hoping will get registers / smbus dump very soon. Edited by gupsterg - 2/7/16 at 4:32pm
As you can see due to the higher voltage they use = less power draw and lower LL effect.
From how you state DPM 0 is 0.993v in bios but show as 1.080v in GPU-Z @ idle, you definitely have voltage offset present in ROM or IR3567B.
Attach your stock ROM to post, so someone may view and also attach i2cdump file.
Thanks for this information, and apologies on my slow response.
Quick follow up:
To change the idle clocks in HR, do I just edit the values in the powerplay tab, and which ones? For instance, to increase the idle mem clock from 150 to 300, do I change the values in Mem clock 3 AND mem freq table @ DPM 0, or just one of those values?
Below are two roms. The first is the stock silent position rom I downloaded from Gigabyte. The second is the same rom, which I slightly changed by adding +25mv to VDDCI in the powerplay tab in HR, and +7mv (1000mv total VID; reported in GPUz is 1015mv; no change to load voltage, haven't set all DPM voltages manually yet) to the idle voltages in all 6 tables. This didn't fix the problem, which I guess may be less voltage related and more idle frequency related in OS X, since I still had the horizontal flashing lines in OS X at the desktop that went away entirely if I ran something in the background (Heaven bench, or 4K youtube video in Chrome) to put the GPU under load.
I've been flashing the silent position rom because I'm very unlikely to use the stock silent position rom, so I'd like to leave the performance position rom (which works well for gaming for now) and modify the silent position.
i'm testing 1375 mem clock: sky diver hang when the girl see the piramid...no black screen,3dmark hang and an error "dx device removed" appear. Every time in the same exact moment. The witcher 3 that maxout the gpu is stable for over 40min.Same with dirt rally and f1 3013.1250mem no problem in 3d mark.
I have tried standard and tight timings, +/-25mv vddci and vddc. Someone have experience with this problem? Edited by generaleramon - 2/8/16 at 3:12am
Cheers for ROM , also thanks for info on RAM , please do provide i2cdump as the info helps .
You are aware if you like, I can mod the "performance" ROM and you can flash to the "silent" ROM position? as the switch is just a switch and the card is not aware what ROM should be at which switch position.
My plan is to give you a modded stock ROM which should just give you the voltage as set in ROM. Included will be a ROM with 390 MC mod as well, your choice which you use and you will do any mods you require on top yourself.
The reason why:-
a) a lot of time I have spent detailing mods in post 1 and want people to use that info. If when they find an issue with instructions there they can post and I will improve it.
b) if people do their own mods I can spend time on exploring other things, otherwise I'm spending time on doing mods which are already detailed.
I hope that is OK .
The Matrix 290X CF owner has stated UK evening time I will receive i2cdumps.
From data from various reviews the 0.95V voltage / VRM freq. adjusment / etc are available on Matrix 290X even without LN2 pad being solder on rear. They are just limited to what they can be set to as detailed in image below.