Please help Gskill F3-12800CL9T-6GBNQ & Gigabyte GA-X58-USB3 cannot use more than 2GB

[GA-X58-USB3]

Hi There,

Please can someone help me this is an obscure/frustrating problem!

My main system is:
Gigabyte GA-X58-USB3 (latest bios rev: F5C)
Core i7-965XE
G.Skill F3-12800CL9T-6GBNQ
Asus GTX480
Corsair TX750W
Intel 120GB 330 Series SSD

Whatever I do I cannot get this system to boot into Windows 7 64bit with all 3 G.Skill Ram modules installed. It will post everytime & you can get into the bios but it will never ever boot into Windows it BSOD's or reboots itself (depending on Bios settings) before the animated Windows logo finishes its cycle.

Things I have tried:

3 x cheap no brand 2GB Ram modules which all work fine in any of the 6 Ram slots on the motherboard to eliminate the motherboard Ram slots.

1 x G.Skill 2GB Ram module from this kit will work fine in Ram Slot 5 but if its put into Ram slot 1 or 3 you cannot post unless you also have the other 2 x G.Skill Ram modules installed into the other Slots to form a Triple Channel config of 6GB (3x2).

All G.Skill 2GB Ram module's from this kit work just fine on their own to eliminate they are not faulty at all.

I have also tried the G.Skill Ram modules in another system I have (Gigabyte GA-X58-UD5 with latest bios F13c & Core i7-980x) & they will not all work together in that motherboard either unless I only use 1 module on its own.

I can only mix n match 1 stick of the G.Skill Ram with 2 x Corsair 1GB DDR3 in the X58-USB3 motherboard & it works & is 100% stable at all times but cannot ever use more than 2 G.Skill Ram sticks together as it will not post the bios & or just goes into a reboot loop.

The only combination of the G.Skill that will work is if its in Ram Slot 5 then regardless of what brand Ram is in the other 5 Ram slots it will always work just fine. This is no good to me obviously as I need Triple Channel DDR3 for max memory bandwidth from my Core i7-965XE (which I have owned from new in 2008 & its always run at stock clocks never been oced apart from the Intel Turbo boost function which takes it to 3.33Ghz on the fly depending on demand).

Disabling all Bios settings for the CPU so it only runs on stock clock speeds makes no difference.

All Bios CPU settings are set to Auto.

Setting the G.Skill to run @ 1.65v makes no difference either (the Bios defaults to 1.5V).

All Bios settings are on Auto anyway for timings (9-9-9-24) but I also tried manual timings 8-8-8-20 & changed the Ram multiplier to x 8 to produce the 1066 this older Core i7-965XE requires but this makes no difference whatsoever.

I cannot see anything obvious which is causing this as all G.Skill ram modules work fine on their own just not together despite the Bios saying they are all present & the timings are all the same. Something is causing them to not boot into Windows 7 64bit & its also a brand new OS re-install but I have dual boot & it will not boot into the 32bit OS either unless its only 1 G.Skill Ram module.

I have looked at the URL given here to troubleshoot this missing capacity (http://i4memory.com/f54/asus-x58-6-1...stalled-19200/) but cannot find anything obvious which applies to my setup.

Please can someone provide some guidance here as to what I can do to get this to work as I cannot see anything else obvious to try I am not an overclocker at all but have a lot of experience with building my own PC's over the past 20 years or so.

Thank in advance.

[Tradesman]

Might want to try running memtest on each stick individually (5-6 passes), sounds like you may have a bad stick, especially if the other set you tried worked OK

[GA-X58-USB3]

All sticks work fine on their own its only when combined they fail to boot Windows. On their own they are 100% stable.

[Tradesman]

How about with 2 sticks? slots 1-3? or 1-5? May have a bad channel or the MC (Memory Controller) might be bad, another check you can do if things are fine in 1-3 or 1-5 would be check the CPU and socket for lint, thermal compound etc, as well as a close look for bent/broken pins

[GA-X58-USB3]

Sorry but it does not work with the G.Skill Ram modules I have bought in those slots but I can put other brand Ram into the same slots with no other changes it works 100% for hours/days.

I can also use any of the 3 G.Skill Ram modules in this motherboard or another & they will work just fine as long as I only use 1 G.Skill on its own regardless of combo with other brand Ram the problems come when I try & combine more than 1 x G.Skill ram module into either motherboard. The G.Skill kit is a triple channel kit BTW so the Ram should be matched right!

I assume the issue is something voltage wise needs tweaking in the bios for all 3 G.Skill ram modules to work together with my Core i7-965XE (which was the 1st Core i7 model released in Nov 2008 & mine is from the first batch I believe as I was one of the first people in my country (England) to buy one as I bought on release day).

Any suggestions regarding what needs looking at voltage wise as it will post to bios with the 3 x G.Skill but never ever boot into Windows so it must be related to the voltages surely as I have eliminated the Ram & all 6 motherboard ram slots.

Could it be a combo of something volts wise needs tweaking on the CPU as well as the Ram (both are set to Auto in the bios)?

[Tradesman]

Have you tried raising the QPI/VTT (MC (Memory Controller) Voltage), I'd guess + 0.05 or so