B550 chipset no 1st or 2nd gen ryzen cpu?

[TheEndIsNear]

I just was wondering why this chipset doesn't support older generation ryzen cpu's. Is there a technical reason that I don't know of. I was troubleshooting a board with a 3900x in it and I had a spare r5 1400 cpu and I was going to use it to test the board but I realized that the cpu isn't supported on b550 chipsets. I was just wondering. It seems odd to have the same socket and not be able to use older processors. Do any of you very smart people know why?

 

[newtekie1]

AFAIK, there isn't a technical reason B550 doesn't support older CPUs. The issue is a BIOS size limitation. A lot of board OEMs were using small sized BIOS chips. This meant that their motherboard could only support so many CPUs. So AMD decided to just cut support for the lower processors from B550, so the motherboard manufacturers could keep using the smaller BIOS chips.

 

[Blue4130]

. It seems odd to have the same socket and not be able to use older processors.

You mean like intel has been doing since nearly forever?

 

[Mescalamba]

Unsure if its possible with this or not, but AGESA codes in general say what CPU it can support, so if you somehow find some suitable ones, or mod them, you can probably make B550 run older Ryzen too.

Im not experienced in modding new BIOSes tho, I did opposite which was adding full 6 core support to old 1366 motherboard, including fixes for Meltdown, Specter and so on, at least what Intel released.

But unless things changed drastically, it shouldnt be that hard to simply swap support of many new CPUs for many old CPUs, as long as mobo can work with it.

 

[Dragokar]

These two ASUS B550 do support Zen and Zen+ CPUs.

TUF GAMING B550-PRO｜Motherboards｜ASUS Global

AMD B550 (Ryzen AM4) ATX gaming motherboard with PCIe 4.0, dual M.2, 14 DrMOS power stages, 2.5 Gb Ethernet, HDMI, DisplayPort, SATA 6 Gbps, Front USB Type-C®, USB 3.2 Gen 2 Type-A and Type-C®, and Aura Sync RGB lighting support

www.asus.com

Pro B550M-C/CSM｜Motherboards｜ASUS Global

AMD B550 (Ryzen AM4) micro ATX business motherboard with enhanced security, reliability and manageability. Dual M.2, PCIe 4.0, 1 Gb Ethernet, dual DP/HDMI, SATA 6 Gbps, USB 3.2 Gen 2 Type-C®.

www.asus.com

 

[bug]

I just was wondering why this chipset doesn't support older generation ryzen cpu's. Is there a technical reason that I don't know of. I was troubleshooting a board with a 3900x in it and I had a spare r5 1400 cpu and I was going to use it to test the board but I realized that the cpu isn't supported on b550 chipsets. I was just wondering. It seems odd to have the same socket and not be able to use older processors. Do any of you very smart people know why?

If the mobo is not very new, it was probably launched with support for older CPUs. You can just flash the older BIOS and you will get support.

But yes, a lot of people took AMD's promise at face value and disregarded the numerous technical hurdles you have to overcome to reuse the same mobo for many generations of CPUs. Those same people seem a little confused, now that reality caught up

 

[Mescalamba]

These two ASUS B550 do support Zen and Zen+ CPUs.

TUF GAMING B550-PRO｜Motherboards｜ASUS Global

AMD B550 (Ryzen AM4) ATX gaming motherboard with PCIe 4.0, dual M.2, 14 DrMOS power stages, 2.5 Gb Ethernet, HDMI, DisplayPort, SATA 6 Gbps, Front USB Type-C®, USB 3.2 Gen 2 Type-A and Type-C®, and Aura Sync RGB lighting support

www.asus.com

Pro B550M-C/CSM｜Motherboards｜ASUS Global

AMD B550 (Ryzen AM4) micro ATX business motherboard with enhanced security, reliability and manageability. Dual M.2, PCIe 4.0, 1 Gb Ethernet, dual DP/HDMI, SATA 6 Gbps, USB 3.2 Gen 2 Type-C®.

www.asus.com

Hm so its just matter of BIOS editing most likely.

 

[The red spirit]

But yes, a lot of people took AMD's promise at face value and disregarded the numerous technical hurdles you have to overcome to reuse the same mobo for many generations of CPUs. Those same people seem a little confused, now that reality caught up

Nah, AMD straight up lied that's it. ADM didn't particularly have problems with AM2, AM2+, AM3, AM3+ and FM2+ platforms and they supported several generations of CPUs just fine. AM4 platforms just wasn't well thought out and thus it has a case of split support.

 

[Dragokar]

It only depends on the SMU inside the AGESA. It is a kinda artificial limitation, and you can check the bios-files before flashing with SMU Checker provided by this german website:

AM4-Plattform-Tool: SMU Checker zum Vorab-Auslesen der SMU-Version - Hardwareluxx

AM4-Plattform-Tool: SMU Checker zum Vorab-Auslesen der SMU-Version.

www.hardwareluxx.de

 

[Deleted member 202104]

It only depends on the SMU inside the AGESA. It is a kinda artificial limitation, and you can check the bios-files before flashing with SMU Checker provided by this german website:

AM4-Plattform-Tool: SMU Checker zum Vorab-Auslesen der SMU-Version - Hardwareluxx

AM4-Plattform-Tool: SMU Checker zum Vorab-Auslesen der SMU-Version.

www.hardwareluxx.de

If the CPUs are listed when examining the BIOS file, does that mean they're supported? For example, here's the output from the latest BIOS file for my board (MSI B550 Unify):

 

[Dragokar]

As far as I can see the microcode is there yes, unfortunately this does not mean it will work. The vendor still have ways to block the boot that's why I recommend those two Asus Boards.

 

[Deleted member 202104]

As far as I can see the microcode is there yes, unfortunately this does not mean it will work. The vendor still have ways to block the boot that's why I recommend those two Asus Boards.

Ah, ok, thanks. That makes sense as the board doesn't show support for most of that list. Unfortunately, I don't have any older CPUs/APUs to test. Appreciate the information.

 

[TheEndIsNear]

Thank you guys. I'll have to try that next time I get a day off.