Above 4G Decoding - What am I missing?

[HarveyHouston]

All right, I need a bit of help on this one. My MSI motherboard supports "Above 4G/Cryptocurrency Mining". I want to enable this, but in trying to boot back into Windows 11, I'm stuck at a boot-loop (i.e. the little circle under the motherboard logo just keeps spinning, and I never get to the Windows user selection screen). So, here's what I know:

• Windows 11 needs to be installed on a GPT-formatted drive. No problem there, all drives on my system are GPT formatted, even my old Ubuntu drive I added from my laptop.
• The BIOS should be up-to-date. I have the latest BIOS for my motherboard.
• This works best on a solid-state drive (SSD). I have a 256GB NVMe PCI-e M.2 drive, so that should work.
• One should either have more than 4GB of GPU memory OR at least 16GB of system memory. AFAIK, I have 2GB of GPU memory, but I should be able to extend that with the 16GB of RAM I have available. Here are my GPU memory specs, as shown by Windows Task Manager:

• This is usually for multiple graphics cards, but it can also work with just one, and it also works with APUs. Performance can vary, meaning sometimes it makes things a bit slower, yet I am willing to see if that is the case - if I can ever boot into Windows, that is! I have no graphics card, but I am using an AMD Ryzen 3 2200G wit Radeon Vega 8 graphics.​
• Finally, it's usually enabled for something called a resizable bar. I have no idea what that means, and my motherboard doesn't even have that in the BIOS anyway... so there.​

The reason I want this is so I can run high-profile applications a bit more smoothly without much lag. I have been doing hours of research on this, with seemingly no progress, and I can't for the life of me figure out why it doesn't work. I know I'm missing something, but I can't figure out what it is. Aside from hardware upgrades (which I'm not against, but I'd rather explore other options first IF available), is there something I'm missing?

 

[PewnyPL]

I don't know why exactly it doesn't work for you. Only thing I can think of is that maybe it enables Resize Bar by default and your GPU is not compatible with it.
Either way, you have only 2GB of dedicated VRAM, so this option literally does nothing for you. Shared memory is just that, your RAM is used by the GPU in addition to VRAM. 4G decoding is used by GPUs with a lot of onboard memory (above 4GB) so they can access more than just the first 4GB of main system RAM to copy texture data onto themselves, which can speed up texture transfers, as the PC needs to load the textures into its main RAM once, instead of load it in 4GB chunks and wait for the GPU to copy it over.

 

[HarveyHouston]

...You have only 2GB of dedicated VRAM, so this option literally does nothing for you.

That's... not what I was hoping for. However, it's hard to find IG memory specs on the APU I'm using, so I'm not sure if 2GB is truly the maximum, or if it's just what is assigned to it - and thus it is actually capable of larger GPU memory, but something's restricting its full potential.

 

[PewnyPL]

That's... not what I was hoping for. However, it's hard to find IG memory specs on the APU I'm using, so I'm not sure if 2GB is truly the maximum, or if it's just what is assigned to it - and thus it is actually capable of larger GPU memory, but something's restricting its full potential.

APUs can be weird about the memory. It's even possible it doesn't have that 2GB either and just Windows report that, completely leeching off of system RAM. In which case, 4G Decoding absolutely wouldn't do anything if it doesn't have its own memory.

 

[HarveyHouston]

APUs can be weird about the memory. It's even possible it doesn't have that 2GB either and just Windows report that, completely leeching off of system RAM. In which case, 4G Decoding absolutely wouldn't do anything if it doesn't have its own memory.

Which could explain why Windows isn't able to boot, because it's looking for an actual GPU with its own memory, and since there isn't one, the result is a boot-loop. It's just a theory, but a plausible one.

Post automatically merged: Oct 20, 2022

Doing a bit more research, this Electronics Hub article actually helped:

How much RAM does APU use?

Since the CPU and GPU are on a single IC, there is no separate memory for the GPU in an APU and it uses the main system memory. Hence, if you are planning to buy an APU, you have to keep in mind that a portion of the main system memory (RAM) is dedicated as Video RAM. We suggest you to have at least 16GB of system memory in dual channel configuration i.e., two 8GB sticks to get a decent performance for your APU.

So, there's two theories I'm proposing:

1. The aforementioned theory; the system is looking for dedicated GPU memory, but a GPU with its own memory doesn't exist... so boot-looping happens.
2. The actual amount of system memory given to the APU, which could possibly handle more memory, is limited by the motherboard, and thus a boot-loop happens because the BIOS simply doesn't have the option to increase GPU memory beyond 4GB (because the maximum is 2GB).

Either way, it looks like I currently have two options:

1. Get an actual GPU, and also a new power supply, since it can only go up to 450 watts. If I invest in one with 4GB or more GPU RAM, then I can use it in conjunction with my APU. This is the costlier option, but simpler, and solves theory 1.
2. Get a new motherboard which will allow for more GPU memory for my processor. More complicated, as it requires nearly undoing my entire system, but may be worth it in the end. This would solve theory 2. Eventually, I may invest in a newer, faster APU for better processing, and perhaps later the GPU and power as mentioned in option 1.