ASUS P5B Deluxe LGA 775 Intel P965 Express ATX Intel Motherboard
G.SKILL 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model F2-6400CL5D-2GBNQ
Scythe SCNJ-1100P 120mm Sleeve CPU Cooler
COOLER MASTER Centurion 5 CAC-T05-WW Black/Silver Aluminum Bezel, SECC Chassis ATX Mid Tower Computer Case
Antec True Power Trio TP3-650 650W ATX12V SLI Certified CrossFire Ready Active PFC Power Supply with Three 12V Rails
Intel Core 2 Duo E6300 Conroe 1.86GHz LGA 775 65W Dual-Core Processor Model BX80557E6300
2 x Seagate Barracuda 7200.10 ST3250620AS 250GB 7200 RPM SATA 3.0Gb/s 3.5" Hard Drive (Perpendicular Recording) -Bare Drive
SAMSUNG 18X DVD±R DVD Burner with LightScribe Black SATA Model SH-S183L LightScribe Support - OEM
Arctic Silver CMQ-22G The high-density, ceramic-based thermal compound
Seagate Barracuda 7200.10 ST3250410AS 250GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model F2-6400CL5D-4GBPQ
MSI ATI Radeon HD4670 1 GB DDR3 VGA/DVI/HDMI PCI-Express Video Card R4670-MD1G
I guess I see myself with 3 options for a minor/major upgrade:
Stay with Intel, Upgrade the board (broke the tab on the PCI-E so might as well), and upgrade CPU but stay with 775
Stay with Intel, Upgrade motherboard, upgrade CPU but go up to LGA 1156 and start on low end with an i3. This would mean buying new memory as well.
Go with AMD. I have zero experience with AMD but I hear you may be able to get more for your money.
Things that go into my decision:
I don't do any gaming (young kids) and that shouldn't change anytime soon. Want to do more home video editing mainly and will also do my SQL development, IT training, and Virtual boxes as well. I'm pretty sure that VMWare and others can really make use of the quad over the dual on virtual instances. I don't really need to worry about the video part of the debate because I won't be going to dual video cards. Also, I don't really care to overclock. I want something that is completely rock solid. That is more important to me right now with family pictures and videos to take care of and time being a big commodity. I thought about listed out my current hypothesis for each option, but I didn't want to taint any expert opinions. I'd love to hear some ideas about which route would be best and especially if I'd be ok going AMD.
Do not spend any more money on the LGA775 socket. You'd be throwing your money way.
After that, it really depends on how much you want to spend. An i3/H55 build (worst for video editing) would run about $300-350. An AMD build (either X4 635 or X4 955) would range from about the same, but the lower end would be essentially equal and the higher end would be more powerful. An i5/P55 build would run above $400, but would be the most powerful of the three.
Something else to point out is that the LGA1156 options wouldn't have an upgrade path. The socket is being replaced in a year, so you won't see anything more come out that you could upgrade to later.
To be honest, I would tend to lean towards the AMD side. There is aboslutely nothing wrong with an AMD build, and it makes more sense right now from a budget and future proof stand point.
The only reason to stay with a 775 system would be to save $100 in RAM expense.
I think that an Athlon IIx4 CPU ($100) and an inexpensive AM3 motherboard (Gigabyte 770TA-UD3 or 870A-UD3, $85-$100) plus a 2x2GB DDR3-1333 RAM kit ($110) is going to get you the best performance for the money. Keep the 4670, PSU and everything else.
Either that or find a AM2+ board that supports the new six core CPU. This would just to hedge your bets that you'd be able to use it with whatever other CPU's that come out for it. That way you could also go ahead and keep using that RAM.