Only 4gb of ram out of 6gb is detected in system info

I just finished building my system and it has an asus p6x58d-e motherboard. an i7 950 processor. windows 7 64 bit.and the ram pc3-12800/1600mhzand patriot sector 7 ram.. At boot it says 4088 or something like that mb of ram OK. When i go to system information i get 2 2gb of physical memory. But if i open up cpu-z and go to memory it says i have 6144mbytes, and it is triple channel, sometimes it says dual, but it is always 6144 mbytes. i tested out teh sticks by trying to boot the system by using 1 stick, and it hung up on 1 stick. What should i do, its pretty irritating knowing what you have isnt being used.