It may be dead but this is a last upgrade for a motherboard. I totally agree with impaledmango. Finish off this which can be done for much less than a complete rebuild would be, and you avoid throwing away money for a mobo and RAM when you will likely have to toss the mobo in the future when intel only releases better stuff for the x58 platform. Not only that, you may be able to wait and leapfrog the "current" stuff that way.
Getting an i5 is only cheaper on the CPU, but not when you have to spend $150-300 on a mobo. The six cores aren't even going to that 1156 platform. That makes it just as useless as a 775 mobo that already has a quad.
I priced out a system for a i5 and a Phenom II 965 for a guy, and it turned out that it was $20 cheaper for the i5. He then found that the i5 wasn't that much faster than the 965 and that AM3 has a MUCH brighter future than 1156, he more or less said screw intel, and bought the 965 with a really high quality $150 AM3 mobo.