You can use that motherboard and CPU combo if you get a new case, however, you should keep a few things in mind. First, you will need to repurchase Windows due to licensing restrictions. That is, unless you have a full, boxed retail copy, not an OEM edition. Second, that is an old motherboard and CPU you have in your link so you are already out-of-date. Third, if you are going to be reusing the your current case, your current motherboard is micro-ATX so you may not be able to fit a standard ATX motherboard inside. With video editing, you may want to get a more powerful RAM, CPU, and motherboard combination.
Motherboard: ASUS M4N68T-M AM3 NVIDIA Geforce 7025/nForce 630a Micro ATX AMD Motherboard
- This is a very basic motherboard for AMD CPU's. It is a micro-ATX motherboard that takes DDR3-1333 or 1600 memory. $49
RAM: G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333
- All AM3-only motherboards require DDR3 memory to run. Remember, with 4GB or more of memory, you need a 64-bit operating system to use it all. $94
CPU: You have a number of choices here to go with your budget. You can get the AMD Phenom II X4 925 Deneb 2.8GHz
($139), AMD Phenom II X4 945 Deneb 3.0GHz
($150), AMD Phenom II X4 955 Black Edition Deneb 3.2GHz
($160), or the best quad core AMD has, the AMD Phenom II X4 965 Black Edition Deneb 3.4GHz
($180). The last two CPU's are Black Edition, which means their multiplier is unlocked making overclocking very easy.