To me this is a really weird behaviour of the system.
Can you try clearing the cmos by removing the motherboard battery and put it back after about 30 minutes. After the clear cmos, power on the system and go to bios and load default settings, save and exit.
If the issue remains, please try to using 1 memory module and remove the sound XIFI sound card and see if it makes any difference.
Please remember to connect the graphics card only on the PCI express port which is nearest to the Chipset heatsink.
If problem remains, can you try with different graphics card and memory, just to make sure they are not the ones causing the issue.
Which bios version are you using and which bios update method are you using? If you have not done it yet, please can you try with the recovery method?
Let us know how it goes.
Hope this will be helpful to you.