I have a question for the brain trust here. I am not very technical when it comes to hardware. However, I want to brave and set my PC to use SAM. My motherboard is tuff x570 wifi plus, I know I will need to update the bios, I have a Samsung sdd 970 evo plus PCIE 3.0. This drive has the OS and games installed. Now I have heard that I will need to separate the game files to another drive. Should I get another m.2 drive? A step by step guide would be great, if it’s not too much to ask. thank you all.
I assume that by SAM you meant Smart Access Memory which is also known as Resizable BAR, or ReBAR.
This is a feature which allows the operating system to read and write to all of the GPU memory instead of only a 256 MB block at a time. Although I believe that the GPU was always able to initiate DMA transfers from any host memory it wanted to, so this was not that big of an issue.
But I am lost as to how your NVMe drive comes into the question. Are you maybe thinking about Windows Direct Storage feature? That sets up data transfers directly from NVMe storage to GPU VRAM. There is demo code doing the same thing in Linux but I don’t know of any standards or libraries to support using it in apps.
Also, I don’t believe that there is any requirement to use SAM with Direct Storage, since the DMA bypasses the BAR anyway. (As far as I know.)
So an update on the issue. My OS is installed on a NVMe drive. For what ever reason when switching the CSM to disabled hid my boot drive. So I can still keep my OS on the NVME and still enable SAM. I’m running windows 10 pro
Any help or advice is greatly appreciated. Just taking small steps to learn this stuff.
CSM is Compatability Support Module. It is required to boot off any drive using the old DOS MBR partition type.
When you turn CSM off, you are using only UEFI. This will require a GPT partition table and a EFI System partition with the boot files.
I think in Windows you can go into the Disk Management tool, right click on your boot drive and convert it to GPT. I am not sure about making a boot partition. It doesn’t matter what order the partitions are in so you can shrink whatever the last partition is, unless its some kind of recovery partition, in order to make room for the EFI System partition. I use about 200 MB for mine.
Oh and before trying anything with disk partitions and such, make sure you have a backup and make sure you have a DVD or USB Thumb Drive that can boot Windows Recovery for you.
I worked out my issue. After I updated my BIOS I didn’t realise that my Windows install was done using the legacy mode. So by following the guide at the link below, I was able to resolve the issue by converting the boot process to UEFI. I can see that the GPU resources have a large memory range, which the guides say signifies that Smart Access Memory is working. Thanks again for the advice.
Thanks, this just helped me sort out a dual-boot system that had a Windows MBR drive and a Linux GPT drive (long, long story.) Now I don’t have to go into the BIOS and twiddle settings every time I want to switch OS’s.
This is a major trap for new (and old) players during the BIOS/UEFI transition which took like 5-10 years longer than it should have - and we’re only really starting to see fall out from UEFI only stuff now.
Many UEFI implementations default to Bios compatibility by default, and as a result many otherwise UEFI capable Windows installs got installed in BIOS mode.
Seriously, PC land is at least a decade (maybe 2?) behind the times here… Mac went EFI based in the PowerPC days.