I have seen this question here and other forums but the reported fixes have not worked for me.
Here's what I have:
Corsair XMS3 6 GB
Windows 7 64bit
Windows shows 6 GB of ram with 4 GB usable. I updated the bios to F5 and unchecked the maximum memory box in msconfig. I checked resource monitor and it shows 2050 of memory in Hardware reserved.
I also pulled the cpu and inspected the motherboard, I could not see any bent pins but there was an are of silver in the middle of the motherboard, I did not see a pin there. Hoping there is not a missing pin.
Any Ideas, if you need more information please ask.
Thanks for your help.
More about :memory problem gigabyte x58a ud3r motherboard
I tried pressing ctrl + f1 but did not get an option for addressable memory. I did figure out the problem though. Memory channel 1 is bad. I tested each stick of memory in channel 1 and it did not boot. I tried memory in only channel3 and only channel 5 and channel 3&5 and they all worked. Looks like a RMA for me.