No worried. The good news is that atx is a standard, the micro atx board should accept the psu no issues. Only issue you may have is fitting the gpu into your case. But the 6600xt usually a fairly smallish card.
Make sure when you get the cpu especially, before installing it, check the motherboard manufacturer’s website. You should be able to download and install the latest bios there. Some boards you will need to install a bridge bios. In other words you may need to install a bios version that then will give capabilities to update to the latest one which will be what the new cpu needs.
If I’m right, is this your board?
https://www.asrock.com/MB/AMD/A320M-HDV R4.0/index.asp#BIOS
When you install things this may be a good way to go.
1. Update the bios. You might need a USB drive.—-if I’m reading correctly, you need
A- install bios version 7.00 as a bridge bios.
B-remove the athlon cpu
C- install the ryzen 5700x
D-upgrade to the latest bios
2. Power it up and test
3. Install the new power supply
4. Install the new gpu. Use ddu to remove old gpu drivers and install the latest ones from amd.com
Note, happened to think of it, I don’t believe the 5700x ships with a cooler, I don’t think the athlon cooler will be adequate. Maybe something like a vetroo v5 would do it. Though I like the Thermalright peerless assassin which is likely overkill but looks cool.
However I’m thinking a down firing cooler for that a320 board is a better idea considering the vrms are probably a weak spot Any thoughts folks?
I’m thinking this cooler might be what the dr ordered. Reviews say people have had good luck with the 5800x3d with this cooler so I’d think it would be more than a match for a 5700x.
https://www.amazon.com/Thermalright-AXP120-X67-Profile-Cooler-TL-C12015W-S/dp/B09ZL6CRCD/ref=mp_s_a_1_19?crid=5SEEBS77SFQT&dib=eyJ2IjoiMSJ9.FKtUdF4vktq8dajHPEkZt8fTv4WRaeQrqjk2FwmGy2cUbXBEC8QyYrJU3a-IRCeITqH8TES-EEsVhP_2vqaZxoPG6eP8CAg2LPH_JNaGMgbaJChwz2Kf05gRe-hHEqnXkcml6yLojGgi-IbtjTLiS4xfaJ9rfikDX5yHxJ4khl0tdR2JKhvy1P62a6g43jWxgIl8FWl9qCQZPQMlGQOxjw.oKGLo5PqQnYSMocKfWBVGIk9BXk_UWdQJRzztuxG78k&dib_tag=se&keywords=thermalright+cpu+cooler&qid=1714515668&sprefix=thermalright+cpu+,aps,93&sr=8-19