Need recommendation on SATA JBOD controller.

I have an LSI 9240-8i and its not compatible with either an Asus 990 FX nor a Taichi x370. It works in my Gigabyte 970, but that board I have no confidence in.

So please recommend me a controller card that is relatively cheap and relatively fast. No fewer than 4 SATA ports. This is for linux software RAID.

I've never used them under Linux, but the Highpoint 2720SGL has served me well under Windows. You can use it as either a RAID adapter or just a HBA, your choice. I ran both a RAID 50 and a RAID 6 array on mine at different times and never had any issue during rebuilds and such. It's not a true hardware controller, but it worked well at least.

I have no problems with LSI 2008 IT cards in x370 or x399, try flashing it and getting rid of the boot rom while you're at it, that is the ideal configuration for zfs/software raid anyways.

The bargain bin/no-name 'just sata port' controllers all suck.