x58 - adding a forth stick of Ram?

[chickadee]

Hey guys,

Currently have a gigabyte UD5 ver1 (old version) X58 board with an i7 920.

I have 3x2gb Kingston 1600mhz RAM. I was looking through the manual and it states that adding a forth stick will work and still run in tri channel.

Since my RAM is older i cant get the same model.

Wondering if I could just add a forth stick that's the same size/speed/timings and still have it run in triple channel?

 

[chickadee]

Think you can only run it on dual channel mode.

The manual states triple using either 3 or 4 sticks. Problem is i cant get an identical stick so it would probably be better buying a dual channel set and removing a single stick from my tri set.