Ga-890fxa-ud7 (rev 2 0) 8GB CONFIG

Are those the default mem timings? If not and if you have made any changes in the BIOS regarding the RAM timings, I'd suggest go back to the defaults and then try it and post an update.
Also make sure you have populated all the RAM slots or than just 2 of them after reading which 2 slots work together.
It is also very important for you to post the exact model number for your RAM cos if you have a Quad Channel ones, then you are going to be able to use only a limited number of sticks if they are compatible....
Although I don't even know if they are compatible with your rig or not....

And it seems like a Typo, but here it just doesn't list the 1600 RAM
http://www.gigabyte.com/products/product-page.aspx?pid=...
The only GEIL 1600 DDR3 Ram this board seems to support are 1GB sticks Model GV32GB1600C8DC, single sided
As the specs say, to go to 1866 and above you need to install the mem in slot 3 and slot 4 so I guess you might need to make some changes in the BIOS to not let this be the basic.... it could be possible that when the system is populated in slots 3&4 it automatically jumps to 1866MHz.... check the manual, and the advanced setting in the BIOS for RAM and it's timings and voltages....

I got this reply from Geil.

Dear Richard,

We use the same IC and modules on GA-890FXA-UD7 (F4) with the DRAM voltage we mentioned
(1.610V) without any questions. If you still have any problems with the modules, we would like to give
you an RMA no. and replace the whole kit.
Thank you.

Regards,

PRODUCT & TECH-SUPPORT CENTER
TEL (886) 2 8227 3260 | FAX (886) 2 8227 3252
16F, NO.268 Lian Cheng Rd., Chung-Ho City, Taipei 235,Taiwan
www.geil.com.tw | www.geil.com.cn
Sent from Taipei, Taiwan

Incidentally, even the A-DATA AX3U1600GB2G9-2G which is on the list of compatible memory has the same problem with slots 3 & 4. The GeIL Black Dragon l GB38GB1600C9QC actually posts with three sticks in slots 1,2,3 using the F4 bios. I tried F5b yesterday but this beta bios will only work with slots 1 & 2 in dual channel or slots 2 & 4 in single channel. I will increase the speed of the memory to 1866MHz and use a voltage of 1.6v later. Thanks for the suggestions.

I will be getting an RMA number from gigabyte. The motherboard is now giving a 88 error code. Based on my reading of the manual it should have been 8D. I will keep you guys posted on the situation.Thanks for the concern.Incedentally I have now reverted to my MSI 790FX GD70 and it works with the 8GB of Geil Black Dragon.

The board was RMAED to gigabyte about a week ago. I wil post an update as soon as it is returned or replaced. Thanks for the interest.

Regards, Tammo.

Best answer selected by fortiscrew.

The motherboard was replaced by gigabyte and my 8GB of black-dragon is working perfectly.This board is a rev 2.1 which is said to support up to DDR3 2000.The memory slots arranged in a different manner as compared with the rev 2.0 and so dual channel mode is achieved in a different manner(slots 1 &3 or 2 &4).Thus ends over 6 months of frustration.I am now an happy gigabyte fan.I take this opportunity to thank you all for your enlightening posts and all the best for the coming year.

Regards, Tammo.

Nice to hear that, enjoy your mobo and I hope see you in Tom's constantly.