ram slots 1 and 2 unusable

[bradp75]

My z170x Gaming 7 mobo won't work in dual channel mode. It gives error code 55. I turned off fast memory boot and was able to boot in slots 1 and 3 but it randomly locks up. Is it the ram or mobo?

This is the second one of these i've went threw! the last one wouldn't boot after setting XMP profile 1 setting in bios version F20. It bricked the board.

The memory is Corsair 8gb LPX vengeance. I checked for bent pins in the cpu socket there fine. Clear coms 3 times. Upped the voltage to the ram to 1.36. Updated bios to F8.What else can i try?

Thinking i'm going to need to RMA this board AGAIN which is getting really frustrating. I can't exchange it with newegg anymore the 30 day exchange period is over . Its gonna take for ever to get a replacement!

Hope someone can help!

[shadowsports]

Are you using memory above 2133Mhz?

[bradp75]

The bios says its running at 2133 , Just load optimized defaults and ran like that.