Even though you bought modules having the same part number, they aren't necessarily identical. Are the chips identical? Loosen the timings a bit and it might resolve the issue.
I am still having issues!
Please tell me how I have to loosen RAM timns (I know nothing about it)!
Now, my bios is:http://i.imgur.com/Pe6PW.jpghttp://i.imgur.com/JmOAX.jpg
Thank you for your instructions!