XP64 and 8GB of RAM crashing. Issues?

I currently have XP64 Pro and 8GB of RAM installed. As far as I know, this should be ok. However, I will get page_fault_in_nonpaged_area errors on disk.sys with a 0x000050 stop code after installing and running certain programs. I ran a harddrive diagnostic, nothing wrong. Then I removed 2 of the 2GB Dual Channel sticks. Voila! I swapped em out for the other two. No problemo! So, my question is, if both sets of RAM work, why is XP64 not happy with the 8GB at certain times? Shouldnt 8GB be supported?

You may have to increase the voltage your RAM is receiving, in your BIOS. I just recently added another 4Gb to my system and it was randomly crashing with blue screens, with the same messages your system was giving.

I had to change my voltage from AUTO to 2.0V. There's something about having 4 x 2Gb sticks that need a little more Umph.

Yes, there are dangers.

The very first thing you should do is download and run CPU-Z and post pics of the memory and SPD tabs, or type out the info if you can't post screens.

If all 4 of your memory slots are populated, it becomes problematic getting RAM to work. If the RAM has low voltage requirements and good general compatibility it can usually be done, with tweaking.

Just increase the RAM voltage by about +.1v. Also are you sure you have set the voltage to the required RAM voltage even? Most high performance DDR2 800 RAM need 2.0v and by default your BIOS only provide 1.8v.