Requesting guideance on PC salvage/build

[MS3Jon]

I am looking at building a new PC using parts from my existing PC. It's a Gateway GM5478 and has been a great computer, but I made a mistake. I installed a BIOS from Intel instead of the correct BIOS from Gateway, and now the BIOS is corrupt and will not reflash. Even though the BIOS was made by Intel for this mobo, Gateway does some weird sh*t with their BIOS, apparently, and now I'm stuck with all kinds of driver and firmware issues as well as PC fans that are running at full blast and are uncontrollable now.
But enough about that. I want to build a new PC but using parts from my PC I have now to ease the price point. The PC has some good hardware and I would like to salvage as much of that as possible. It has an Intel Core 2 Quad Q6600 processor, upgraded the graphics to an NVidia GeForce 9600GT/OC, as well as 4GB of Kingston DDR2/1066 RAM. I know it's not mind blowing hardware but I mainly use my PC for photo editing as I run my own Photography business, and I don't really do any gaming on my PC. So basically I am looking for a motherboard and case that will house this hardware and give me a little room to grow. I would like to eventually get another GeForce 9600 and run them in SLI and have room to expand the RAM to at least 8GB.
I will include some screen shots from Speccy that detail my current hardware in case I am forgetting anything. I have an "above average" knowledge of PC's but have never attempted building a PC. Just want to make sure I'm not overlooking anything, spending more money than I need to, or attempting to tackle an unnecessary job. Thanks for any help you guys/gals can provide!

[glc]

Please repost your images as links, we prefer that on these forums in respect for members with limited bandwidths and screen resolutions. Thank you!

A couple notes - SLI does absolutely nothing for you outside of games. When you need a stronger video card for whatever reason, you will be much better off just replacing the single card with a new current technology single card. In order to run SLI with an Intel socket 775 processor, you need a motherboard with a Nvidia chipset, which is not particularly stable.

Do you want a bare budget upgrade - just a case and motherboard - or do you want to plan for the future and go for an i5 or i7? To do that, you will need a processor and new ram in addition to case and motherboard. This would allow SLI if needed, but I really don't know what a pair of old 9600's would do for you. If you want a stronger processor, I'd recommend the full upgrade, it will be more economical in the long run.

If you reuse your hard drive, you will need a new OS, you can't move the Gateway preinstall to a new motherboard. You should be able to reuse your optical drive or drives as long as they have standard rectangular front bezels.

Do you have a budget number in mind?

[MS3Jon]

I apologize for the photos, I'll get links and post them back.

I guess SLI shouldn't be a selling point for me then, since I don't play games on my PC. The Gateway was handling large photo editing jobs rather easily before this happened. So I don't need much more than I already had. I just would like to give myself a little bit of room to grow, but not break the bank. I've been looking at motherboards but I want to make sure I get one that will use all of the hardware I currently have. I would like to try to stay under $300. Is that possible?

[glc]

Case/power supply:

Antec Sonata III 500 Black 0.8mm cold rolled steel ATX Mid Tower Computer Case 500W Power Supply - Retail
http://www.newegg.com/Product/Produc...82E16811129024

Motherboard:

ASUS P5Q Pro Turbo LGA 775 Intel P45 ATX Intel Motherboard - Retail
http://www.newegg.com/Product/Produc...82E16813131377

Your future CPU upgrades will be very limited.

[MS3Jon]

How about this? Is there any reason this will not work in my situation?

Mobo
http://www.newegg.com/Product/Produc...82E16813128358

Case w/PS
http://www.newegg.com/Product/ComboD...t=Combo.342484