Ask ten people, get eleven opinions.
Intel vs AMD arguments never get old, and are as stupid as they always were. Buy AMD for cost. If you want to spend money, buy Intel. Or, better yet, if you want cheap, just get an atom - they're quite nice these days, and you might find one for like $40, except they're not socketed.
The 4960x or 5960x is a halo product. It is not intended to be bought in quantity. It costs a thousand bucks because it can. On employee discount, they were around $440. (The 4770k/4790k are around $180.) There's no point arguing about its specs or cost because it's so far outside the normal conversation that the arguments are irrelevant; you buy it because you have legitimate need for a workstation or because you have cash to burn (or if you get it for free like I did.) On the other hand, the lowest-end i7 extreme is just for cheap workstations with no on-die graphics and is a legitimate competitor to the highest i7 (4790k today).
It'd be like talking about how silly it is to buy, I don't know, a Bugatti. Nobody buys it because it's a reasonable thing to buy. It exists as a halo product. You buy it because you can.
If you want to talk tech, though, Intel's 140W TDP is not the same as AMD's - Intel's chips are far better at clock gating and power gating to reduce average power consumption. You would have to compare total power consumption, per chip, per task/benchmark, and you'd also have to figure out the power consumption of the rest of the system to compensate (mobo + everything on it). TDP is nearly meaningless these days, TDP is the number which the board needs to handle, the PSU needs to supply, and the cooler has to cool over long periods. Over short periods, TDP can be massively exceeded. TDP is what happens when you launch a task to fill up the CPU and leave it for an hour. This is why most chip vendors - TI, Samsung, Qualcomm, etc - don't publish TDPs as such; they publish spreadsheets with a bunch of variables where you can figure out approximate TDPs depending on usage scenarios.
PS, broadwell is not socketed really. So you're not going to see socketed broadwell. Broadwell is also a clusterfuck because they gave the design to the Bangalore team. Quite a few broadwell products are shipping but they are of course all soldered to laptop/tablet/convertible motherboards. Broadwell will mostly skip the desktop. You're thinking of Skylake which will be socketed.
Oh, and the old single- versus multi-threaded performance argument. One, it's fairly silly to argue that AMD has better multi-threaded performance. Since it's a question of specs, you can see pretty easily... 8 cores is as much of a misnomer as thinking that 4 hyperthreaded cores are really 8 cores; both share resources. Two, cores are also not apples-to-oranges comparisons, despite Nvidia's claims to the contrary - an 8-bit ALU is not a core - and you'd have to study the architecture to figure out what's better for what. We're talking differences in out-of-order engines and buffers, how many ports it has, how wide each core is, what instructions it enables and what ones you're likely to use, how much cache is available, and so on... and so on... Three, most of your programs are single-threaded, will remain single-threaded, and bottlenecks are single-threaded performance. Both AMD and Intel can turbo cores briefly to help with this. They can do fun stuff like turbo a single core, then when it heats up transfer the entire process to another core. Of course, memory access then often becomes the real bottleneck: how fast can they get and push data? That's why overclocking like crazy is usually pointless; your chip runs faster but it still takes the same amount of time to get data from main memory so you're sitting there with your thumb up your ass burning power.
TL;DR: Chip design guy tells you chip design is super complicated and can't be summarized with platitudes when hard-to-understand specs change every year.
FarmerPete, your current rig is pretty decent as is. Where are you being held back? That's the main question. I'd probably upgrade RAM first. My system is constantly using 10+ gigs and having a lot helps.
