look into a SSD for your OS and programs use a few 1T drives for your storage and backup
Have you considered a nVidia GPU with CUDA ?
As stated above I already have 4670 VGA and will play NO games, so not at all interested in swapping video card. I also stated above, I already have WD 750GB sata HDD and my main question was whether i need more than 3Gb of ram for what I plan to do, so 8GB is certainly useless.
8 gigs of ram wont be useless when your doing photo/editing work Anyways.
32 bit OS wont see more then 3.5 gigs of ram IF you need to use more then that go with a 64 bit OS
If you go with a s1366 mobo go 6 gigs if s1156 go 4 gigs
And your post Stats $1,500 best build - help needed So If you dont need a new HDD GPU PSU Should of lowered your budget, Because just because you have that dont meen it is the best for a 1500 dallor system.
And where the hell did i say swap the GPU for games ? i said ( Have you considered a nVidia GPU with CUDA ) Photoshop can use CUDA
You said ( Now, I need help with MoBo, CPU and memory, meaning I'm undecided between the 775 and 1366 rig. I heard a ton of argument pro and con both systems) If you dont want to consider a s1156 as a opition with a i7 860 Then go for a s1366 because the s775 is EOL and they will be phasing it out
If you're into professional, heavy duty photo and video editing, 8GB is great. But for occasional editing and general use, 4GB is the sweet spot. 3GB is a bit on the low side, and that'd mean taking a 1366 motherboard, aka a dumb purchase.
-Intel i5-750 CPU
-1156 mobo of choice
-4GB of RAM
-A slightly better graka (CUDA can be useful, but that's a bit overkill). But since more and more apps are becoming GPU assisted (even the next generation of firefox and internet explorer), a good graphics card will become a performance booster even in a non gaming machine. No need for a beastly card, but a decent mid-range one is handy. Consider one of the lower mid end Nvidia or ATI ones (GTS 240 or 4850 for example).
-As said above, consider an SSD. It will massively speed up your OS and your most frequently used programs. An intel 80GB one will be the best purchase you've ever thought off. Of course, only do this if budget allows for. Good old mechanical hard drives are slower, but good enough and at a lower cost.