what gpu are you using rn?
8gb amd rx vega 64 sapphire nitro
i flashed it successfully and enabled above 4G - disabled csm
but cant get rebar to work from ReBarState.exe
can you provide older bios web page link for this MB?
sure, here you are the both links to the original one .cap and updated one in .Rom:
choose the one that will work best
Hey everyone,
I’m hoping to enable ReBAR on my MSI Z97-S02 motherboard (MS-7821) with an i7-4790k and an Arc A770 GPU (I know, quite a mismatch between GPU and CPU but I got the card cheap from a friend, so I am trying to make due before I upgrade my whole PC). I saw there’s a file floating around for the Z97 Gaming 7 that enables ReBAR, but I’m hesitant to try it on my board in case there are any incompatibilities despite the same chipset. I am unsure if the difference in VRM, PCIE slots or audio and connectivity stuff might cause issues. Would that modded BIOS work on my Z97-S02, or am I risking bricking my motherboard?
If using the Gaming 7 BIOS file is not advisable, could someone with BIOS modding experience guide me through creating a modified version of my Z97-S02 BIOS with ReBAR support?
Any help or advice would be greatly appreciated!
(LINKS)
Modded bios for the Gaming 7 version: [Request] Resizable Bar for MSI Z97 Gaming 7
My motherboard and its specs: MotherboardDB
Thanks, Gabriel
When using the guide to find the right var offset numbers etc. ifrextractor extracts over 11 .txt files and I can’t find anything of value in them. I used the latest downloadable file from MSI’s website.
I have tried both UEFITOOL and UEFITOOL NE.
Also asked MSI for a BIOS with the 4G Decoding option but they said it wasn’t available.
Hello @BasedGabe o/
Above 4G Decode appears to be in the Setup already.
It’s in the Advanced > PCI Subsystem settings
Are you able to see this menu in the bios setup?
Hello @68k-dude,
Thanks a lot for the fast reply!
Well, that’s the tricky part, there’s no such option in my bios. Maybe it was to make miners buy a more expensive motherboard back in the day, who knows.
See the picture for an overlook of my bios (ignore ram values etc, I just bricked my system after trying to change the var offset and it didn’t work. The values I found seem to be funky)
Hi @BasedGabe ,
There are two Advanced menus it appears.
I wonder if there is a keyboard combo to get into the more advanced Advanced menu 
Thanks for the tip @68k-dude ! I can only find shortcuts for people who have MSI laptops and I can’t find any information about the Z97 s02. Could I instead, even if it seemingly is an available setting, just change the var offset? I’d appreciate if you could take a look and maybe find the right values.
Edit: Searching for MMIO, 4G Decod, Above 4G all yields results. Anyone else with an MSI motherboard who can chip in and explain what they did to enable 4G decoding (as it’s seemingly hidden)
Hi @BasedGabe,
Have you looked into the program called AMIBCP ?
That’s the screenshot I sent you up above.
You can make changes to the Default and Optimal settings.
You could set Above 4G Decode to be enabled by Default or in the Optimal settings.
I would try setting it to ON in the Optimal only at first, just in the case where it makes the system unable to boot.
Do you have any way to recover from a failed modification? An external programmer?
Hello @68k-dude ,
Unfortunately I don’t have an external programmer. However, from my understanding, many people have successfully gotten MSI z97 motherboards to support rebar. Even if my particular motherboard is a budget variant, I doubt it would be any different. I know that I am doing this at my own risk, and I want to be careful, but I believe it’s worth a shot.
If I use AMIBCP and change the Above 4G Decode setting to on in optimal, would a simple CMOS reset make the system bootable if it becomes unbootable due to the change?
Thanks again for the help, it’s very appreciated.
EDIT: When trying to open the latest BIOS file AMIBCP says “The input image is not Aptio V”? In your screenshot you successfully opened it so I am not sure there’s any need for another tool like this: GitHub - BoringBoredom/UEFI-Editor: Aptio V UEFI Editor: an alternative to AMIBCP
Hi @BasedGabe,
That’s the plan. A CMOS reset should load the Failsafe defaults. So If when you set it to ON in the Optimal settings and there is an issue, you can recover it.
You need AMIBCP 4.55 to open Aptio IV files.
Hi @68k-dude ,
Wow, I am sorry for the oversight. Of course I need a version number that starts with 4 if I am working with Aptio IV files… I changed the optimal settings to enabled.
I suppose all I need to do is put the new file on a USB and flash via m-flash in my current bios setup menu, right? If the system boots then it’s enabled and working, otherwise I reset CMOS and it reverts back to failsafe values, correct?
Sorry if I sound stupid. Trust me, I am usually smarter than this! 
H @68k-dude,
Followed all the steps. It flashed successfully. Afterwards there’s simply a black screen, nothing happens. Not even bios splash screen shows up.
I am 100% sure that I put failsafe value at disabled. Yet when I turn the Psu off, remove power cable and remove cmos battery I still get a black screen (black as in getting video output but it’s black, not black as in no display).
Seems like this board might be bricked. If that’s the case then it’s not that big of a deal, I’ll simply upgrade my PC.
oh no 
you need to leave everything unplugged for a few minutes after cmos bat remove