I couldn't even get $100 for my 750 and board a couple years ago. I ended up giving it to my sister I was so mad at the lowball offers. Maybe $75 for that CPU and board. Maybe.
Ram is unknown. How many sticks? Is it three sets of 2x4GB? That makes the most sense considering your tri channel board. I don't think 2x4GB sets of DDR3 sells for very much though. And due to the tri channel board you'll either need to sell it all with the board, or three of your 6 sticks. Getting rid of the extra memory could pay off, or be a giant pain. Looking online I see these going for anywhere from $30-$75. (difference is speed.) $40x3 sets is $120 for the ram.
The card and PSU are basically junk. You have a Dell really, and the PSU is probably better off sold with the board. It's also probably nothing fancy, 80+ bronze. I sold my Antec 750W Green PSU years ago for $45. And that one should run on any after market system. I'd honestly try to sell that PSU with the board for an extra $40-50. The card is mega junk. Take any offer you get. $25-$50 or so is what I'd guess.
The drives are probably nothing special also. Might get $50 or $60 for the pair. Last I looked my Samsung 470 120GB was worth around $40. 1TB spinning drives are $20 all day long.
There should also be a case. My guess is like the PSU it should go with the board for the same reasons. $20? Add all this up and you are looking at around $350? Did that in my head so I might be a bit off.