Sapphire RX 480 NITRO+ OC 4GB not working properly

[SpenzeR]

Hi

I am pretty new to mining and all but I've really tried to search all over the web and tried figure this out on my own.

I have 2 x Sapphire RX 480 NITRO+ OC 4GB now at first I am just trying to modify the secondary gpu. And when all is successful I will do the same with my primary gpu.

I am running:
- Win 10 64 bit
- Crimson 16.11.5 drivers
- GPU SKU: 11260-02-20G
- Miner: Claymore's Dual Ethereum+Decred_Siacoin_Lbry_Pascal AMD+NVIDIA GPU Miner v9.5

So first of all this is the gpu were it says "4GB" on a sticker on that package, but it's removable, and behind that sticker it says 8GB, so from what I've red it got the same hardware as a 8GB and therefore it can be flashed to 8GB.

This is what I've done so far:

1. I backed up all bios roms.
2. Turned off the rig, and switched the vbios switch towards the hdmi ports.
3. Then I made a copy of my bios rom and changed the memory value from 4096 to 8192 I also changed the memory strap timings. I copied the value at 1625 and used that value at 1750, 1900 and 2000.
4. I then flashed it using atiflash.
5. After this I saw some performance gain when dual mining ETH+SIA with Claymores dual miner. Eth went from 24 Mh/s to 25 Mh/s and SIA was the same as before (680 Mh/s).
6. Now what I saw people recommended was undervolting the gpu, increase the memory clock and reduce the core clock. Now this is when I am getting problems.
7. My original settings was, core clock @ 1266 and memory clock @ 1750. I have only changed the memory clock and set it to 1810.

I've tried undervolting it (-6 at a time), tried increasing the memory clock and reduce core clock (1220 - 1250) but nothing seems to work longer then a few minutes (if I am lucky) then it will crash and give me bsod.

I saw someone with the same card suggesting to set -96 mV, 1220 core, 2100 memory my pc instant crashes if I do so.

I've also tried copying the timing straps from 1500 and set them at 1625, 1750, 1900 and 2000 and do the changes above and it still gives me the same problem.

Any idea why I can't touch the voltage or core clock without everything crashing?


Current GPU-Z stats while mining @ 25 Mh/s ETH & 680 Mh/s SIA

https://i.gyazo.com/1a12b89b51d349a3a15fa1f00d3d9bf5.png

https://i.gyazo.com/cb01233e9d15a62e4b2f76e98e7c9026.png

[fraggyb]

The only cards that you can flash to 8GB from 4GB are the original 480 reference cards and the Nitro+ isn't one of them, I own it myself.  It's quite standard now for companies to use one box for all their cards and just slap a sticker over the ram.

I would really do more research before doing anything like modding and flashing your cards bios, you're going to end up bricking your cards.  Flash them back to the stock bios and overclock with msi afterburner or the like for now while you do research.

For example, googling your cards make/model would have told you can't flash it to an 8GB.  I'm just glad you did it totally wrong or you would have most likely fucked your cards.

[SpenzeR]

The only cards that you can flash to 8GB from 4GB are the original 480 reference cards and the Nitro+ isn't one of them, I own it myself.  It's quite standard now for companies to use one box for all their cards and just slap a sticker over the ram.

I would really do more research before doing anything like modding and flashing your cards bios, you're going to end up bricking your cards.  Flash them back to the stock bios and overclock with msi afterburner or the like for now while you do research.

For example, googling your cards make/model would have told you can't flash it to an 8GB.  I'm just glad you did it totally wrong or you would have most likely fucked your cards.

Hi, dont know if I am allowed to link to another forum site (please correct my post if it's against the rules), but I found the guide here:

https://forum.ethereum.org/discussion/11159/rx-480-sapphire-nitro-oc-4gb-modded-to-8gb-31-mh-1225-2200-mhz

You are sure this is wrong and not possible? Both cards is detected as 8 GB cards in the system now, all softwares are confirming it being 8 GB (gpu z, claymore, other hw softwares).

[fraggyb]

Glancing at that it appears he's just changed information that is displayed.  Pretty sure you could change that value to anything and it'll show.

I guess you could try running a game that uses a lot of vram and check with RTSS if it's using more than 4096MB.

[fraggyb]

This is the bios I'm using https://anorak.tech/t/anoraks-vbios-collection-optimized-settings-for-performance-power-saving/13

The Memshift version gives me 30Mh/s on my 4GB Nitro+

https://i.imgur.com/HLnVUKS.jpg

[SpenzeR]

This is the bios I'm using https://anorak.tech/t/anoraks-vbios-collection-optimized-settings-for-performance-power-saving/13

The Memshift version gives me 30Mh/s on my 4GB Nitro+

https://i.imgur.com/HLnVUKS.jpg

Nice, thanks for helping out. I need to try that one. Have reverted the 8gb flash, so I am back to 4gb now.

Could you check if the bios version and memory type that you see on my gpu-z image in my first post match yours?

[coinzoid]

Actually, this card (if Samsung chip) can be flashed to 8GB version. I've two of these cards and both working well with flashed bios. I've optimized the bios by comparing Jukebox low power version and getting 29.3 ETH and 460 Sia on average.

[SpenzeR]

Actually, this card (if Samsung chip) can be flashed to 8GB version. I've two of these cards and both working well with flashed bios. I've optimized the bios by comparing Jukebox low power version and getting 29.3 ETH and 460 Sia on average.

Nice, yes it got samsung memory. Would you care to share your mod?

[SpenzeR]

This is the bios I'm using https://anorak.tech/t/anoraks-vbios-collection-optimized-settings-for-performance-power-saving/13

The Memshift version gives me 30Mh/s on my 4GB Nitro+

https://i.imgur.com/HLnVUKS.jpg

I tried the same setup as you have now.

Flashed bios using: Anoraks_Sapphire RX 480 Nitro(plus) 4GB Samsung_memshift.rom
Driver Version: Crimson ReLive 17.5.1 (had to patch it using atikmdag patcher 1.4.5 if not it only threw error 43 in device manager)
Used same afterburner version as you (4.3.0) and set the same values as you (core clock: 1150 mhz, memory clock: 2125 mhz, power limit +15)

Started claymore miner (ETH only) with the following command:

EthDcrMiner64.exe -epool eu1.ethermine.org:4444 -ewal 0xMYWALLETADDRESS -epsw x -esm 1 -asm 0 -mode 1 -tt 74 -tstop 85 -gser 2 -eres 2

And it crashes instant when it's about to start mining. All goes black and I have to reboot my pc.

Any suggestions?

[fraggyb]

Try a lower memory clock and work your way up a few mhz at a time.

[SpenzeR]

Try a lower memory clock and work your way up a few mhz at a time.

Thanks, you've pointed me in the right direction, getting 27 Mh/s from each now.

Appreciate it!

[SpenzeR]

Okay so I've been trying alot of different settings now.

Setting the following in afterburner:

mV: -72
Core: 1125
Memory: 1900

Gives this result

Watt: 85 watt
Eth: 27.8 Mh/s


However it only runs for about 5-10 minutes, then one of the gpu's stops, and the system crashes.

Any suggestions, I've been going from -48 mV to -72 mV, do I need to go further down? Like -96 mV?