It has 5 pcie slots, however I've succeeded getting only 4 cards to work in Win10.
This is not the issue though - the most disturbing is latest MB bioses produce random freezes of the machine!!!
It took me a while to figure this out...
Instead of latest ver3.4 I've flashed ver2.5 and so far it seems to be fine.
There's no direct link to such an old version, I had to guess the filename on asrock ftp.
Used this one as a reference: ftp://europe.asrock.com/BIOS/FM2+/FM2A88X Pro+(3.40)WIN.zip and replaced "3.40" with "2.50"
This is not the issue though - the most disturbing is latest MB bioses produce random freezes of the machine!!!
It took me a while to figure this out...
Instead of latest ver3.4 I've flashed ver2.5 and so far it seems to be fine.
There's no direct link to such an old version, I had to guess the filename on asrock ftp.
Used this one as a reference: ftp://europe.asrock.com/BIOS/FM2+/FM2A88X Pro+(3.40)WIN.zip and replaced "3.40" with "2.50"