So there are basically 3 levels of chips,
ASIC - developed at the hardware level for certain functions, data comes in and is processed, then comes out. But you can't change anything, once the chip made there is no flexibility. Extremely fast, no flexibility.
FPGA - like an ASIC processing is done in the chip but it is flexible and can be programmed for different needs. Also extremely fast, depending on the need may not be as fast as an ASIC, very flexible. Extremely Fast and flexible comes at a price.
X86/ARM Processor (intel, AMD, etc) - relies on software to tell it what to do, which is slower, but you ca almost anything with them. Slower with ultimate flexibility.
Not really.
ASICs are just any chip foundried with a fixed function. Processors and GPUs are technically ASICs - just that their fixed function come together in such a way that they implement one or more programmable processors.
FPGAs are different in that they are composed of IO, logic and memory that can be linked together in (almost) arbitrary ways to implement specific function, via a programmable fabric (that often can only be re-configured at boot, though some partial reconfiguration is possible in some devices).
If you happen to need the operations implemented exactly as they are in the CPU/GPU, it is likely to be the fastest option available (as the processor manufacturers are at the bleeding edge of process advances), but the reality is most jobs don't need things exactly as implemented in a CPU or GPU, so it gets much harder to benchmark... A CPU implemented in an FPGA would be slower for a similarly affordable FPGA.
There are whole papers on trying to compare the raw performance, performance per $ and performance per watt, and you need to know so much about the workload it is generally speaking impossible for the layman to have any idea whether a given tech is better for a given workload.
There are many other factors in selecting devices - such as what clocking reqs you have, what IO you need, thermal considerations, what tech your engineers have expertise to deliver a solution on... The list goes on. Attempting to reduce these to binary "is A better than B" is pointless.
The RRP $ of the FPGA used in the Lumagen VP is more than the sum total of all the hardware used in the Envy combined.
Not really a fair comparison though, because no-one buying any volume of FPGA is paying anything at all remotely like the retail price - the difference is MASSIVE between retail and what is known as "supported pricing", yet the PC market parts are commodity and there is very little margin available on them for a PC building shop, with the pricing very well known.
I'd imagine the net result is probably a not massively different overall cost.
