Just received this case SKTC A09. Had a hard time building this because of the space constraint, just 3.8L. I had to remove the front panel and the modular PSU bracket to install in the Flex 1U PSU. My advice is to just get a non-modular 150mm long Flex PSU for ease of installation. Shipping was fast, just 1 week from Taobao to Singapore.
SKTC A09 ~$17
Biostar Motherboard ~$125
Ryzen 5600G Box ~ $225
Shipping ~$12
The PSU and RAM are from my parts bin.
I thought I could just slide in the power supply. But the two lower motherboard stand-off was preventing it and the width of this case is just 9mm wider than the PSU.
Motherboard is the BIOSTAR B550T-Silver. Came with the latest BIOS (B55AK730.BSS) and works with Ryzen 5600G. Haven't heard much about BIOSTAR for quite a while. Thought it went extinct like ABIT.