guys up to how many sata port can you use in p5w dh?

it seems that i can only use
the 3 near the south bridge
and one ez raid on the right coz when i use both even i enable it on bios it doenst detect the one on the left
also i noticed the one near the processor is a little bit slow let say only 1-2mb/sec on the hdd tach but when i put the hdd on the other slot it goes upto 219+