My AMD Phenom 2 X4 940 BE does not recognize my dual channel

What bios are you using? The option for ganged exists inside the first selection. (M.I.T.) The setting is called "DCT's Mode" and can be set to ganged or unganged.

BTW: Other than for benchmarking there is no reason to set it to ganged mode. Ganged will give you less than a percent of performance increase on single threaded applications; multi-threaded applications or normal system use will be slightly slower with ganged mode. Unganged would be where most people set it for all normal use. (Which is also why it defaults to unganged.)

(ALSO: Most ram will always be detected at 800mhz. Always. You must specifically either set the ram to 1066 OR turn on the EPP Mode to "AUTO" which will allow the BIOS to read the ram's EPP profile. That setting defaults do disabled. Either way you then either need to manually set the VDIMM or turn the EPP VOLTAGE setting to ENABLED.)

Update the bios. I have a Gigabyte Mobo that came with Bios that wouldn't activate Dual Channel and I am running Corsair Dominator DDR2 1066. Update the bios the go into the memory setup and enable ganged mode (dual channel). It works fine and yes the CPU does support it.

The Phenom can easily run DDR2 at 1066 in dual channel.

Some people do have problems if they fill all 4 of their memory slots. Although some people have no problem running at 1066 with all four slots filled.

But generally with only two memory slots DDR2-1066 will run at 1066 without any problems. Especially with the second generation of the 790 chipset motherboards. (Like the UD4H.)

Although I would recommend setting the timings by hand so that you set the tRFC to 195ns. (Often the default of 127.5ns works okay, but 195ns is generally more stable. Especially if you are going to overclock.)

The F2 bios is the newest one available on the UD4H. (It was released 2 weeks ago.)

The Phenom should be left in unganged mode if you are only running 2 sticks of memory. This allows the dual memory controllers on the Phenom to work independantly of each other, supposed to be faster. It you have 4 sticks, so you are running 2 banks in dual channel, then each memory controller will run a bank, and then dual channel mode should be enabled.
BTW, my 920 on my Gigabyte board runs at 1066 without doing anything, detects it automatically, and sets my 2 sticks to unganged, as it should be.
could it be possible your BOIS needs updating? If the voltage requirement is like 2.1 volts, I would opt for some better memory. (not saying OCZ is bad memory, but if you have turn the voltage up to get it to run at 1066, meh....there is better memory out there) My Crucial runs at 1066 at stock voltage, 1.8.

__AMD__,

I have the same board and processor, paired with two 1GB sticks of Kingston HyperX DDR2 1066 (KHX8500D2K2/2GN). I would really appreciate it if you could let me know exactly what settings you had to change to get your BIOS to post at 1066. Cheers!

Here's what I've got:





I should note that above 'DDRII Timing Items', the setting 'DCTs Mode [Unganged]' is cut off.

Thanks!
-Kp