Question PC keeps power cycling on and off, NO POST

[jeidenL]

Hi!
First off, I am completely new to PC building, so please bear with my minimal knowledge.

My PC specs are:
Ryzen 5 5600

ASrock B450m Steel Legend
2 x 16gb DDR4 3200mHz Ram
Asus Dual RX6600
Thermaltake P650B PSU
512gb M.2 Nvme
2Tb HDD

As this is my first PC build, I am completely stumped with what to do. So far I've done the following to try and fix the issue.

1. Taking the CMOS battery out and clearing CMOS with the two pins on the MOBO
2. Reseated both RAM sticks. Also tried with 1 stick.
3. Checked that every cable was in properly and so forth.

I am getting my friend's spare PSU to test if my PSU is the problem, but I have a hunch that this isn't the problem. I've come to the conclusion that the problem could be the MOBO.

Would an outdated BIOS be causing my PC to be power cycling on and off?

Also, a general question. When I plugged in the RX6600 the fans don't initially spin, is this a problem with the card or does the card only spin when reached a certain temperature?

Any help will be appreciated!

 

[kerberos_20]

b450 mainboards were initialy released for ryzen 2000 processors, later bios updates extended CPU support up to latest AM4 5000 CPUs, so it may be possible that your mainboard needs bios update,there should be sticker on bios chip with bios version on it, it is very small sticker like 5 milimetters small (US measurement would be...as big as ladybug hehe), with something like P1.30 on it, whatever is there is bios version
5600 will need bios version P4.30 at minimum, so if youre on 2.x/3.x etc bios versions(lower than 4.3), then bios update is needed

for your second no fan gpu issue, thats a feature, no heat on gpu = no fan