Ok, I could do what I have done before since Apple finally caught up with the rest of the world and used x86 processors, I can install Windows on an Apple box natively rather than mess around with virtualisation. But fundamentally the same problem remains, do they have a single box that is both affordable and has multiple socket CPU configurations? As far as I'm concerned, any form of software clustering, or virtual CPU distribution is no solution. Even if it were technically viable, a bag of apples isn't going to be cost effective.
To reiterate, I am not trying to build a top500 cluster for peanuts. I want a higher power desktop without paying server level money.
To help indicate what I was hoping exists, but I assume does not, this is the last dual socket box I built:

Here you see two Prestonia 2.4 GHz processors on an Asus PC DL motherboard. This was rather unique as it used a desktop chipset not a server one to provide the dual CPU support. The Presonias were mid generation netburst Xeon processors with HT, which were an easy overclock to 3.2 GHz. I was running a 2 CPU 4 thread system at 3.2 GHz in 2004. Dual core in a single socket didn't come along for another year, which eventually negated the need for dual socket in the affordable enthusiast market and I don't recall seeing anything like it since.
I have also evaluated the other options. AMD X6 processors are just generationally too old. My stock SB i7-2600k has as much throughput as my overclocked X6 at 3.5 GHz. From reports out there, Bulldozer is worse even with the two extra so called cores, they really cheaped out on the shared FPU design which cripples it from anything I want to run, as most geekier software is still heavy on the FPU and not integer instructions as focused on by AMD. So that leaves SB, IB and server variants thereof as possible upgrade options.