F3-12800CL9-4GBSR & Gigabyte GA-P55A-UD5 not working together...help!!

[Godzilla]

Hi All,
Well, I got the need to up my RAM from my current, original and long running 8Gb Corsair [4 x TW3X4G1600C9D] to newer and faster RAM that totals 16Gb. So far I have tried 3 different sets of G-Skills all of which have behaved the same and that is failure to boot, no BIOS access...nothing. Maybe a blinking cursor if I am lucky. Yet each set will work just fine if it is installed as 8Gb [2 x 4Gb] in the correct pair of slots in dual channel mode. When the original RAM is put back in it boots and runs as before with no problems so I have ruled out any motherboard issues.

Current G-Skill RAM is G-Skill F3-12800CL9-4GBSR...one of the Sniper versions as this specifically mentioned my motherboard on the web site. I currently have just 2 x 4Gb sticks installed with total stability but would like the other 2 x 4Gb as well.

I have been trying out different combinations of the G-Skill RAM today to make sure it is OK and there is no problem with any combination of the four sticks I have. They all work perfectly well with each other in any combination and run at the correct spec but that is ONLY when installed in dual channel mode. Once I introduce a third or fourth stick it will not boot. I have no access to change anything in the BIOS as it will not get that far.

I am assuming that I should change the BIOS settings when I only have two sticks installed then between reboots put in the other two...correct? I will have to do more research on the settings before trying anything.

Is there something obvious or obscure that I am meant to know or do? Some BIOS tweak or setting that is needed? Sacrifice to the computing Gods? Can someone assist with this difficulty?

System is:
Operating System: Windows 7 64bit SP1
Motherboard: Gigabyte GA-P55A-UD5
CPU: Intel Core i7 860
BIOS: Latest F12 [there is an F13beta available]
Graphics: XFX Radeon HD 5770
New RAM: 2 x 4Gb G-Skill F3-12800CL9-4GBSR [currently installed and running but will change to something faster when I get this sorted]
Old RAM: 4 x 2Gb Corsair TW3X4G1600C9D
Drives: Drive #1 - ST3500320AS (465 GB)
Drive #2 - WDC WD1001FALS-00J7B1 (931 GB)
Drive #3 - WDC WD5000AAKS-65YGA0 (465 GB)
Drive #4 - WDC WD1001FALS-00J7B1 (931 GB)

A very vanilla, standard type of system with nothing overclocked. I still have not heard back from Gigabyte after my questions to them.

[Tradesman]

To run two sets of 8GB, you may have to raise DRAM voltage by about .05 and will probably need to raise QPI/VTT about .075 or so

[Godzilla]

To run two sets of 8GB, you may have to raise DRAM voltage by about .05 and will probably need to raise QPI/VTT about .075 or so

Thanks for the reply. So to run my 4 x 4Gb modules I would set the above values in the BIOS when it is running with just the 2 x 4Gb, then shutdown, install the other 2 x 4Gb modules and boot up again?

I will give it a try when I get a bit more time but until then I will continue my web search as I do not believe I am unique in having this difficulty and someone...somewhere will have posted something.

Gigabyte got back to me with a 'its all too hard for us' email suggesting I go and look for answers anywhere else but them....gee thanks for that Gigabyte!

[GSKILL TECH]

Install the memory first, then make the changes for four modules. If you get stuck, you can just reset the BIOS and try again.

Proper settings will boot just fine.

Thank you
GSKILL TECH

[Godzilla]

Hi,
Sorry but that can't be done. With all four installed at once it will not boot to give me access to the BIOS. It just hangs or it might keep rebooting. I might get the Gigabyte boot logo showing me the options for BIOS access but it will not respond when the keys are pushed.

I can only get into the BIOS with two modules installed.

Am starting to think of returning to my original RAM and just save the money for something else....but I do have a curious nature and a stubborn mind so I will probably persevere when I get more time.


Thanks.

[GSKILL TECH]

Input the settings with 2 modules, then insert the other two afterwards. If problem persists, try DDR3-1333 8-8-8-24 1.50V.

If this has a problem, send the memory in for RMA to see if two new kits can work better together.

Thank you
GSKILL TECH

[Godzilla]

Hi All,
With thanks to all who offered help and to all who gave it a look. I have fixed the situation by swapping, yet again, the RAM modules for another brand. They are exactly the same spec as the ones I have been trying...only difference was my computer booted first time...

Why is this so??? I have no idea!! I think my motherboard is just fussy and in future I think I will build my next computer with NO upgrade in the future in mind....build it how I want it FIRST time....but then there are no guarantees it will work.

When you consider the almost infinite number of parts available to make a computer out of it is a wonder that anything works...compatibility issues anyone?

Anyway, thanks again for the help and sorry I just do not have the time to tinker about getting things working...I just need it to work so that I can get on with my work...