Topic: One way to undervolt R9 300 series cards by BIOS mod - page 4. (Read 27092 times)
The question is still there. Is it possible to mod memory voltage (not core or aux voltage) on Hawaii via bios editing?
Hello there, I followed the instructions of the op to undervolt my Gigabyte r9 390, but when I read the voltage values in the gpu freq table here is what I got :
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
Simply put:-
In all stock ROMs only DPM 0 is manually set VID, so in your example you see 900 (DEC) and unit is mV.
DPM 1 - 7 in all stock ROMs is "auto calculated" VID, the numbers 6528x represents that, the last digit is basically ID of DPM.
Also note in ROM we are setting VID , what we see in software monitoring is VDDC. VID is what the GPU is set to, VDDC is realtime voltage, this will variate due to PowerTune tech / LoadLine Calibration.
I'll test this as soon as possible.
Thank you for the advice.
Thank you for the advice.
Hello there, I followed the instructions of the op to undervolt my Gigabyte r9 390, but when I read the voltage values in the gpu freq table here is what I got :
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
It is very safe to do. For my XFX 1015 MHz, I use the similar voltage as the OP, but is generally lower.
OP is left mine right.
1000 800
1000 825
1050 850
1050 900
1100 950
1100 975
1100 1000
1106 1050
Yup, should be good!
In the example given here, you give the DPM's a fixed state. It'll do the trick!
Just be careful though, it could be that 1.05v is not enough power to handle 1025 core clock. All depends on your gpu.
Hello there, I followed the instructions of the op to undervolt my Gigabyte r9 390, but when I read the voltage values in the gpu freq table here is what I got :
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
It is very safe to do. For my XFX 1015 MHz, I use the similar voltage as the OP, but is generally lower.
OP is left mine right.
1000 800
1000 825
1050 850
1050 900
1100 950
1100 975
1100 1000
1106 1050
Hello there, I followed the instructions of the op to undervolt my Gigabyte r9 390, but when I read the voltage values in the gpu freq table here is what I got :
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
0 0xA49D 300 Mhz 24-bit 0xA4A0 900
1 0xA4A2 525 Mhz 24-bit 0xA4A5 65282
2 0xA4A7 723 Mhz 24-bit 0xA4AA 65283
3 0xA4AC 883 Mhz 24-bit 0xA4AF 65284
4 0xA4B1 924 Mhz 24-bit 0xA4B4 65285
5 0xA4B6 960 Mhz 24-bit 0xA4B9 65286
6 0xA4BB 994 Mhz 24-bit 0xA4BE 65287
7 0xA4C0 1025 Mhz 24-bit 0xA4C3 65288
As you can see, excepting state 0, the other state voltages are not what I was waiting for.
Do you think it's safe to try values comparable to the values of the op ?
All good mate 
, I lurk here on and off and hadn't been here in a while. Then when I saw this and didn't recognise user name I thought I'd been hacked .
, I lurk here on and off and hadn't been here in a while. Then when I saw this and didn't recognise user name I thought I'd been hacked . However, Due to adding those bytes:-
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
WOW, I'm thinking these are my words
.haha, they are!
However, Due to adding those bytes:-
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
WOW, I'm thinking these are my words
. Eliovp, I had a look at the XFX 1015MHz BIOS you mod for Marvel. I search edfor the 8d 00 xx 00, I could not find that. Did you mod the Core or the memory voltage?
I remember you said both -100 mV for Core and memory.
I remember you said both -100 mV for Core and memory.
I didn't add those values, i only changed the DPM states.
Looking back at those, i will report back with a new one next week because it seems that i failed miserably on that one "XFX 390 for Marvel".
Greetings
Eliovp, I had a look at the XFX 1015MHz BIOS you mod for Marvel. I search edfor the 8d 00 xx 00, I could not find that. Did you mod the Core or the memory voltage?
I remember you said both -100 mV for Core and memory.
I remember you said both -100 mV for Core and memory.
So I first need to find the location of the VoltageObjectInfo.
To search for the start and length of the VoltageObjectInfo table I figure I need to locate the position of the following pattern: xx 00 03 01 01 03
where xx is the length in bytes of that table? (obviously omitting xx in the search pattern)
And then to see if I have a voltage offset entry, look for pattern 8d 00 xx 00 (omitting xx which is the actual voltage offset value)
within the VoltageObjectInfo table. Correct?
To search for the start and length of the VoltageObjectInfo table I figure I need to locate the position of the following pattern: xx 00 03 01 01 03
where xx is the length in bytes of that table? (obviously omitting xx in the search pattern)
And then to see if I have a voltage offset entry, look for pattern 8d 00 xx 00 (omitting xx which is the actual voltage offset value)
within the VoltageObjectInfo table. Correct?
Atomic output will give you the offset location. It's all there
, just open HxD and hit search, enter the offset there and it'll point you to the exact point If 8D 00 xx 00 isn't there, that means that "or it just isn't possible to mod, or you need to add that yourself", keep in mind, it's not just adding it into the rom, you'd have to follow some other steps to complete that process (as i stated before)
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
If it's there, then you just need to edit "xx" as i told you before
If 8E is also there (is always right behind 8D) then you can also mod the memory voltage given to the controller.
Greetings!
Hi Eliovp,
So its a one byte signed value? I.e. F0 = -16 decimal. Then I have to muliply by 6.25 to get -100mV offset value
and voila?
If that is all then I've got it and thanks a lot!
So its a one byte signed value? I.e. F0 = -16 decimal. Then I have to muliply by 6.25 to get -100mV offset value
and voila?
If that is all then I've got it and thanks a lot!
-100 = F0 ---- 100 / 6.25 = 16, -16 in hex = F0
-150 = E8
-175 = E4
So yeah you're right
The offset you want, for example -50, devide 50 by 6.25, make your result negative, so -8, convert that to hex and you have your value
Again, if you're going to mod roms, be sure that the correct offset for core voltage and/or mem voltage is available.
If not, it's possible (in some cases) to add that yourself.
However, Due to adding those bytes:-
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
So in other words, it's not "that" easy :p
Are you able to change the Core or the Memory in the GPU tweek software such as MSI afterburner after your fixed voltage mod?
Yup, that's not a problem at all
So I first need to find the location of the VoltageObjectInfo.
To search for the start and length of the VoltageObjectInfo table I figure I need to locate the position of the following pattern: xx 00 03 01 01 03
where xx is the length in bytes of that table? (obviously omitting xx in the search pattern)
And then to see if I have a voltage offset entry, look for pattern 8d 00 xx 00 (omitting xx which is the actual voltage offset value)
within the VoltageObjectInfo table. Correct?
Do you have a link to atomicbiosreader? I am interested in trying mod my XFX BIOS of the 1050 MHz black edition.
Hi Boathouse
You can find a link to the atombios reader here
http://www.overclock.net/t/1561372/lightbox/post/24069731/id/2549733
Look for the AtomBiosReader section.
How much power does not memory consume when doing Ethereum at 1500 MHz? If it is over 30W, then it is better to under volt it.
Do you have a link to atomicbiosreader? I am interested in trying mod my XFX BIOS of the 1050 MHz black edition.
What is the position of the memory voltage setting in the BIOS file. I am interested in changing that.
open your rom with atomicbiosreader, you can find the offset location for the voltage settings in the .txt file that gets generated.
you'll have to watch out though, not every rom has these values, my nano roms didn't have them, i had to add them myself.
What is the position of the memory voltage setting in the BIOS file. I am interested in changing that.
Hi Eliovp,
So its a one byte signed value? I.e. F0 = -16 decimal. Then I have to muliply by 6.25 to get -100mV offset value
and voila?
If that is all then I've got it and thanks a lot!
So its a one byte signed value? I.e. F0 = -16 decimal. Then I have to muliply by 6.25 to get -100mV offset value
and voila?
If that is all then I've got it and thanks a lot!
-100 = F0 ---- 100 / 6.25 = 16, -16 in hex = F0
-150 = E8
-175 = E4
So yeah you're right
The offset you want, for example -50, devide 50 by 6.25, make your result negative, so -8, convert that to hex and you have your value
Again, if you're going to mod roms, be sure that the correct offset for core voltage and/or mem voltage is available.
If not, it's possible (in some cases) to add that yourself.
However, Due to adding those bytes:-
- you need to correct table length for VoltageObjectInfo.
- the pointer within VoltageObjectInfo to i2c programming data would need updating as well.
- you also then need to remove the same amount of empty bytes to make UEFI/GOP at right offset location.
- directory of data/command tables would need updating in ROM to correct offset pointers to the tables as they would have shifted.
So in other words, it's not "that" easy :p
Are you able to change the Core or the Memory in the GPU tweek software such as MSI afterburner after your fixed voltage mod?
Yup, that's not a problem at all
Are you able to change the Core or the Memory in the GPU tweek software such as MSI afterburner after your fixed voltage mod?
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