DDR2 1066 BIOS setting problems

I just recently custom built a new machine that takes DDR2 1066 and I read that settings in the BIOS have to be tweaked or else it will be recognized as DDR2 800. I am having some major problems...

When I change the FSBRAM ratio from 1:2 to 1:2.66, my machine will not boot... I have to take that little battery out of the motherboard.

This is the main problem I have encountered. Any help would be appreciated.

MSI 790XT-G45
AMD Phenom X4 9950 Black Edition
OCZ Reaper HPC DDR2 1066
Nvidia GeForce 8800 GTS

The BIOS is American Megatrends

With FSB/DRAM Ratio set to 1:2.66 = Adjusted DRAM Frequency of 533MHz (DDR2-1066), change the four primary DRAM timings (CAS Latency (CL), tRCD, tRP, and tRAS) to 5-5-5-15, w/ DRAM Voltage set to 2.1-2.3V. Also change 1T/2T Memory Timing (Command Rate) to 2T. And you shouldn't need to remove the battery after a failed POST. Instead reset CMOS by shorting 2-3 pin of JBAT1 while the system is off, then return to the 1-2 pin position after about a minute.

I did encounter a problem......
I can't change the DRAM Voltage, it's set to [Auto] and will not let me change it.

With the DRAM Voltage option highlighted, you can't change the value by using the + and - numpad keys?

Yeah the option is there but it is greyed out. I tried the -/+ keys and pressing Enter.

You said before that the FSB/DRAM Ratio set to 1:2.66 = Adjusted DRAM Frequency of 533MHz. My BIOS says the Adjusted value is 1066MHz. Does that mean anything?

Sorry for my lack of knowledge, I've never messed with memory before and have very little knowledge of all the stuff. But thanks for your help.
Here's a couple screenshots if they help

Try the Page Up and Page Down keys. And according the CPU-Z pic. you posted, the RAM is currently running at 400MHz (DDR2-800).

Okay so Page Up and Page Down do work. haha

This still does not work!!!

I set fsb:dram to 1:2.66. in the DRAM Configuration I set the timing from Auto to DCT0 and change CL, tRCD, tRP, tRAS to 5-5-5-15 and set tRC to 26 and CR to 2T. I changed the memory voltage to 2.13v. when all this didnt work i set voltage to 2.08. continued to not work so i set tRFC values to 195ns. still didnt work.

what the hell am i doing wrong?! my computer does not like it when i set the FSB DRAM ratio to 1:2.66. it either gives me a blue screen or tells me an important system file is corrupt and windows doesnt start.

btw i am running Windows XP x64 Edition

I would say to set the ram speed to 800 and then go in and set the ram timings to 5-5-5-15-26 2T. First see if those ram timings show up in CPU-Z so you know that you are setting them properly. If so then I would try the 1066 speed at 6-6-6-18-28 2T at 2.1 volts and see if it will work. If CL6 works then you could try to lock the timings down one by one. If that doesn't work your only other option would be to set the ram back to 5-5-5-15-26 2T and do some old fashioned HTRef OC'ing to get the ram speed up as high as possible.

Try changing DRAM Timing Mode to Both, instead of just DCT 0.