Recently I bought a Asrock B450M Pro4-F R2.0 motherboard. The bios it shipped with is v2.80, so for windows 11 support I tried to flash the v2.90. But the problem is it can’t detect the bios in Instant flash mode, says no image file detected.
I can’t figure out wtf is wrong with this thing, later I discovered the most weird effing thing. The bios it has is the regular Asrock B450M Pro4-F not R2.0. I checked the box, even on the marking beside the ram slot, it clearly shows that I have the Rev 2.0 version. Simply put, I have a Asrock B450M Pro4-F R2.0 motherboard with Asrock B450M Pro4-F bios.
This is why it can’t detect the v2.90 as the last version bios of regular Pro4-F is v2.80.
I can’t put it into RMA as I didn’t bought it from proper channel (3rd party), they don’t provide any kind warranty. The board is brand new, unboxed when shipped to me and working fine so far but the problem is it has wrong bios.
So, how do I flash the correct bios? any help would be appreciated. 
How did you got to that conclusion, the R2.0 also has a version 2.80 as the R1.0…both version were released in same date for the 2 models… so nothing wrong here.
The label seems to be a sticker only with the model (R2.0), the revision seems to be on the pcb… if its all in the sticker then i would get suspicious.
A “Bios image not detected” is not a sign of wrong bios model, so i see no validation in your claims.
First of all the usb must be in fat32 format. and the bios must not be renamed.
Do it and retry to flash it 2.90 (better to flash it to 3.10).
In case that the bios chip has wrong bios that i doubt you will need a hardware flasher.
I’m 100% sure. Here is the proof how did I find it. I put both R1.0 and R2.0 bios in a usb drive just like this screenshot, then boot to the bios and instant flash. Look what I have got screenshot, only the bios of R1.0 is showing, it can’t detect the R2.0 bios. Even I flashed the R1.0 v2.70 bios without any problem. @MeatWar @boombastik
Now the proof that I have the R2.0 hardware, picture of the mobo, clearly says Rev 2.0. Another proof is the the marking place itself. The R1.0 has the marking between the two PCIE slot whereas the R2.0 has the marking beside Ram slot. So, I have a R2.0 mobo shipped with R1.0 bios. @MeatWar @boombastik
Sorry I have to post this on new reply cause new users can’t put more than 2 link in one post.
Indeed seems a legit R2.0 by looking at the PCB…
Try the 2.90 or the 3.10 like previously mentioned by boombastik and see what is reported or make and share an FPT dump of the current spi bios in system to check it.
The R1.0 could work in the R2.0 but it was misflashed or programmed by another user or inserted a pré-programmed SPI chip with a R1.0 bios
R1.0 v2.80 (B45MP4F2.80): BIOS Date: 05/10/2021 18:41:19 Ver: A2170280
R2.0 v2.80 (B45M4F22.80): BIOS Date: 05/10/2021 18:47:59 Ver: A2543280
The best solution contact the asrock support and tell that the Asrock B450M Pro4-F R2.0 has 3.10 bios with windows 11 support and ask them to update the Asrock B450M Pro4-F bios, with 11 support. In two days you will have it, and flash it.
-ASRock > Contact Us