I am employing Corsair 8GB KIT, 4 components of model CM2x2G6400C4DHX, 4-4-4-12, 2T, 2,1V version. 1.2...

I distorted in BIOS only these values...because the other standards that can be changed in AI Tweaker ( BIOS-P5Q-E) I can not discover any certification about them....

So your help is very helpful if you have some options to check.

You didn't start with the perfect kits (components that run at 1.8V-1.9V are favored), but you should attempt 5-5-5-15 timings.

As I can observe these memory components are completed to but used with 4-4-4-12 2T, 2,1V. But anyway I will change the ASUS mainboard with several Gigabytes that is working without these troubles.

I have a P5Q Deluxe and a Gigabyte GA-EP45-UD3P (and others) derived from the similar chipset. The Asus is a bit more particular, but don't anticipate the Gigabyte (you didn't say which one and not all are created identical) to run them perfectly. The modules are designed to sprint at 4-4-4-12 2T, 2.1V when 2 modules are installed. When mounting 4 modules, you need to run them with more voltage (I wouldn't because they require too much voltage) or, as I suggested, untie the timings. You could also run them at 667 MHz and you perhaps won't notice the presentation dissimilarity. You're not the only one having matters with 8 GB of CM2X2048-6400C4DHX.

If I sprint them at 667 should I remain the same timing 4-4-4-12 and the similar voltage 2,1V or you recommend other values?

First I would attempt 5-5-5-18 at 800 MHz. Then I'd attempt 4-4-4-12 at 667 MHz and 2.1V. If stable (memtext86+ for numerous hours), lower the voltage pending you start receiving memory errors. Then augment the voltage reverse to a stable value. The goal is to obtain a steady system.

Since I employ quality PSUs, I never ran into that kind of matter. What PSU did you have? I'm asking because that's expensive information for other members.

It was a 540W PSU Zalman.... Now I have a stronger, 650W.... but the difference can be on other parameters too.... But anyway is very strange that ASUS support never asked about this item ...and only sent me to their QVL inspite of my description of memory I used...... Very unprofessional, very bad quality.... "Chineeze" if I desire to describe only in one word.