1) Motherboards are rated by size, and shape, by a Form Factor.
Common Form Factor for motherboards is ATX.
ATX form factor is 12 Inches by 9.6 Inches, or 305mm by 244mm.
(9.6 Inches is about 9 and 9/16ths Inches. -> .625 is 9/16ths of an Inch)
Next in line for common motherboard Form Factors, is the Micro-ATX form factor. 9.6 Inches by 9.6 Inches. (244mm by 244mm)
Using these variables, the next factor that needs to be checked, is if the motherboard has a Socket T processor socket.
Also known as the LGA 775 processor(CPU) socket.
Now you need to find a motherboard, that has a motherboard chipset, that will support the Intel Core2 Quad Q6700.
[FixYa has just undergone site changes. I am not able to post a link, as a direct link; at the moment.
I'll have to ask you to copy the URL (Link), paste it in your address bar (http://), and press the Enter key ]http://en.wikipedia.org/wiki/Motherboard_form_factor
The following is a list of Intel motherboard chipsets, that support an Intel Core2 Quad Q6700,http://en.wikipedia.org/wiki/List_of_Intel_chipsets#Core_2_chipsets
Start with the Intel 975X chipset. Scroll down through the various chipsets, and see which ones support Intel Quad Core processors (CPU's)
The following is a list of Nvidia chipsets, that support the Intel Core2 Quad Q6700,http://en.wikipedia.org/wiki/Comparison_of_Nvidia_chipsets#For_Intel_processors_3
Start with the 700 series, go to the 900 series.
The following is a list of ATI chipsets, that support the Intel Core2 Quad Q6700,
I wouldn't use a motherboard with a VIA chipset. Just my personal opinion.
You also need to find a motherboard, that will use the current Ram Memory you have. Unless you wish to move up to DDR3 Sdram ram memory, and are not currently using it now.
Using DDR2 Sdram ram memory? Then this is one example,http://www.newegg.com/Product/Product.aspx?Item=N82E16813157337
[Just in case; How to Copy and Paste:
Let's use the last link as an example,http://www.newegg.com/Product/Product.aspx?Item=N82E16813157337
Put your mouse cursor on the h, of the http://
Press, and hold the left mouse button down. Slide your mouse across, so the mouse cursor goes across the link. (The link is a URL)
The link is now highlighted in Blue. Hold the CTRL key down, and tap once on the c key. (Small case -> c )
Put your mouse cursor in your address bar. (Starts with http:// at the top of your page)
Press the v key. (Paste key)
Now press the Enter key ]
For additional questions please post in a Comment.
(Unless that is scr-ewed up too, lol!)