Windows 7 Home Premium 64 bit RAM issues.

It sounds like you may have built this computer yourself. If that is the case, I wouldn't necessarily worry about upgrading the BIOS. If you can build your own PCs, then you certainly have the capabilities needed to upgrade your BIOS. It is really a no-brainer operation. I believe you mainly just have to hope you don't get a loss of power during the process.

I looked at the specs for your memory and your motherboard manual. While I didn't see the memory specifically listed as supported at:

http://download.gigabyte.us/FileList/Memory/motherboard_memory_ga-n650sli-ds4.

I don't think you need to worry. In the above mentioned document, Gigabyte specifically says “Due to massive memory models on the market, we can only verify some of them.”

Looking at your Motherboard manual,

http://download.gigabyte.us/FileList/Manual/motherboard_manual_ga-n650sli_ds4_e.pdf

I see that you need “800/667/533 unbuffered DIMMs” at 1.8V for a max of 8 GB memory. I'm pretty sure the Corsair XMS2 memory you are referring to is 800 MHZ DDR2 @ 1.8V:

http://www.corsair.com/products/xms2/default.aspx

so there isn't any reason why it wouldn't work correctly in your motherboard.

Given all of this and the fact that your computer works fine below 4 GB, I'm **pretty**sure this is a BIOS issue. I **think**the BIOS update you want is version F5 or higher, but if I was doing the flash, I would just go for broke and try version F8F**I think** which can be gotten here:

http://download.gigabyte.us/FileList/BIOS/motherboard_bios_ga-n650sli-ds4_f8f.exe

I really can't give you any advice on the process of upgrading your BIOS other than:

1. Shutdown all unnecessary programs.
2. Make sure power is stable.
3. Don't even touch your computer until everything is done.
4. Get or borrow a UPS if you can

I can't find any great articles on how to flash BIOS. All I found was:

http://www.devhardware.com/c/a/Hardware-Guides/Why-and-How-to-Flash-Your-BIOS/2/

You would want to pay special attention to the precautions section of the document.

In the unlikely event that something goes wrong, you will probably have send your motherboard back to the manufacturer or buy a new one. This isn't nearly as bad as it sounds though since:

a) you appear to be a hobbyist system builder

b) Gigabyte Socket 775 Motherboards start at $50http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=4410109&CatId=1572

But as always, you need to verify the links that I provided you on your own. As far as I know, I have provided you with correct information, but it is your responsibility to exercise sound judgment. Since I am a unpaid volunteer, I can not be held responsible for any errors that either you or I might make during this process or acts of God.

Warning:

Absolutely no warranty express or implied comes with this post. The poster will not be held liable for any physical, mental, emotional or financial loss that results from the use of suggestions or information contained in this post. Entities that follow the advise in this post do so at their own risk.