Intel legacy BIOS support removal?

Valnar

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Back in 2017, Intel announced it would remove legacy BIOS support and CSM, and force everyone to UEFI. The dates were "2020".

https://www.anandtech.com/show/12068/intel-to-remove-bios-support-from-uefi-by-2020
https://www.intel.com/content/dam/s...-Boot-Support-Removal-for-Intel-Platforms.pdf

Does anyone know if Intel followed through on this? What chipsets today would be affected?

I'd like to buy the last motherboard/chipset combo that supported legacy BIOS but having a hard time finding that information.
 

Valnar

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Dual boot OS system and want to upgrade motherboard with minimal changes. I'll worry about UEFI the next time around.

If anyone has a 400 series chipset motherboard (Comet Lake), can you check your BIOS?
 
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I have a Rocket Lake motherboard (MSI Z590-A PRO) and it has something called CSM that allows me to boot a non-EFI operating system. However, it will not boot from NVMe drives (so you need SATA), and it requires a graphics card to be installed. Is that the same legacy support you're talking about or is this different?

I'm thinking they're waiting until Alder Lake to do that, if they do it at all. That's when they'll be moving to a chiplet design, 10nm process, possibly PCI-E 5.0 and DDR5. That's why I bought in now, I don't know that my old stuff will be compatible with anything after Rocket Lake. I've heard some motherboard manufacturers eliminated it early, but it appears that motherboard manufacturers can still enable it if they want.
 
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Luke M

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My MSI B460 doesn't support CPU graphics in classic BIOS (CSM) mode. I don't know if that's because Intel dropped support, or if it's a MSI specific thing.
 

GiGaBiTe

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My MSI B460 doesn't support CPU graphics in classic BIOS (CSM) mode. I don't know if that's because Intel dropped support, or if it's a MSI specific thing.

For a video device to work on a motherboard with a legacy BIOS, or in CSM mode, it needs a VGA option ROM to initialize the card. Most video cards/IGPs for the last few years have dropped legacy BIOS support and only have UEFI ROMs, though there are some cards that have both available. I believe Intel dropped legacy VGA ROMs in their latest IGPs, which is why it won't work in CSM mode.
 

Luke M

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For a video device to work on a motherboard with a legacy BIOS, or in CSM mode, it needs a VGA option ROM to initialize the card. Most video cards/IGPs for the last few years have dropped legacy BIOS support and only have UEFI ROMs, though there are some cards that have both available. I believe Intel dropped legacy VGA ROMs in their latest IGPs, which is why it won't work in CSM mode.

Ok but I'm not talking about the latest (Xe)....this is the old Gen graphics.
 

OFaceSIG

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If you have specific needs for BIOS support, you may need to virtualize.
 

GiGaBiTe

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Ok but I'm not talking about the latest (Xe)....this is the old Gen graphics.

I'm not talking about Xe graphics, the older HD/UHD graphics IGPs have in some cases not had BIOS support either. I had an HP machine not too long ago with an i7-4770 where the IGP didn't work in BIOS mode.
 
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I'm not talking about Xe graphics, the older HD/UHD graphics IGPs have in some cases not had BIOS support either. I had an HP machine not too long ago with an i7-4770 where the IGP didn't work in BIOS mode.
Yeah, as far as I know that's not a new thing. I don't recall the IGP working in BIOS mode on a 3770K either. I did want someone else with an older chip to confirm that, though. I think it's because the BIOS they're emulating is sort of a "classic PC" mode, and traditionally PCs didn't have graphics integrated right into the processor and it had to go over the PCI/ISA bus for that functionality. Breaking that would presumably break backwards compatibility. Yes, I know integrated graphics aren't new, but before UEFI I think they were always a separate chip on the motherboard that took up lanes like a peripheral. So in other words... on-chip graphics might very well be one of the things you need UEFI to get because it breaks compatibility with traditional BIOS. I know that you can't boot from GPT formatted drives on CSM/BIOS either for a similar reason, and I think it also dislikes NVMe because... well, traditional PCs didn't have that either, so you probably need a SATA drive.

So it looks like if our experiences are representative, CSM/BIOS still works perfectly with Rocket Lake just like always, provided your GPU is old enough or legacy-friendly enough. My newest GPU is a 670, so I have no idea when they started dropping the Option ROM on GPUs.
 

GiGaBiTe

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Yeah, as far as I know that's not a new thing. I don't recall the IGP working in BIOS mode on a 3770K either. I did want someone else with an older chip to confirm that, though.

I have a few boards with various second gen core i series and one i3-3220 that works in BIOS mode. I think it's up to the vendor if they want to have CSM compatibility. It'd make sense for the DIY market to support both for greater compatibility, but not for HP or other OEMs that only have a specific use case in mind to only run Windows.

I also have a Z97 motherboard with an i5-4430 that the IGP works in BIOS mode.
 
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