Question B450 tomahawk NON max + ryzen 7 5700x3D not POSTing

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Mega19

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Oct 19, 2015
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Hello, good day

i got myself a R7 5700x3D to upgrade from my R7 3700x for my machine, and use it on my B450 tomahawk (non max ver.)

Before anything i updated my MB BIOS to the latest beta as it appeared on the CPU compatibility listed on the official product page, version is "7C02v1J5(Beta version)".

BIOS update went fine, version appears on the BIOS information i and thought, "im set lets change it"
the installation went smooth, no bent pins on new CPU changed, removed cooler, clean up, re-apply paste, etc.

Moment of truth comes by, i turn on the machine with the new CPU, lights turn on, none of the MB error LEDS stay on so i thought i was clear but then simply no POST, its all a black screen...

i waited for approx 10-15 minutes... nothing. still black, restarted and still nothing. all black, In the end i switched back to my 3700x
machine boots just fine with no hiccups, and so i come here to ask for guidance before i possibly take the wrong decision

Im just really hoping this is not the second DOA cpu i buy...

Machine specs are as follow:
CPU: R7 3700x -> upgrading to R7 5700x3D
GPU: RTX 3060 Ti
MB: b450 tomahawk (non MAX)
RAM: Corsair vengeance LED 2x8 (16GB) 3200mhz
PSU: seasonic focus GX 850W
Storage: NVME Western digital blue SN580 1TB, SSD Crucial MX500, Seagate HDD 1TB
 
Solution
Forget the QVL list, few kits are ever listed there anyhow and the list is never updated beyond the first couple of months after the board is released. What is the ACTUAL model of your memory kit, although, honestly I've not seen incompatible memory cause it to black screen. Generally it will just blue screen or default to JEDEC specs. Sometimes a continuous boot loop. But not usually just, nothing, so long as it is the right TYPE of memory, which it is if it works fine with the other CPU.

Where did you buy the CPU? New or used?

As for the BIOS reset, this is the procedure I like to use. It has worked well, even when other methods have not, for many years.

BIOS Hard Reset procedure

Power off the unit, switch...

Mega19

Distinguished
Oct 19, 2015
30
3
18,545
Thanks for your answer I will try this as well and fingers crossed! Also, did you notice any perfromance drops (i.e., the CPU not boosting properly or lower benchmarks scores) due to the older Bios version that theoretically is before the 5700X3D release?
i have not ran any benchmarks on this CPU, but on regular use in games i have not seen drops in performance, just increases, for example FFXIV no longer struggles to keep consistent 60 FPS, the 3700x could barely keep 45 frames in heavily player populated areas