For my part, an i7 will be more efficient. As far as the graphics card is concerned, the problem comes from the driver. Gaming graphics cards are not at all made to run professional applications. They are optimized for gaming. So I advise you to look into a pro series. The quadro series at nvidia.
Look at the Hp, Dell, Lenovo workstations... Even with your budget you should be able to have a configuration that will have the advantage of having a pro CPU (Xeon), a pro graphics card, in short components optimized for the work. And I want to say above all assistance in case of problems.
When you see the benchmark results, often the pro processors are not the best located in pure results. Xeons are much more expensive for a possible negligible gain.
For the graphics card I would be less sure of myself, the drivers of the pro cards are indeed optimized for solidworks but as for the same price you have either a CG pro (equipped with a low-end gamer CG processor) or a gamer CG with a high-end processor (at least a high-end one), the gain of optimization will not necessarily be felt (the CG gamer will not be optimized but as it has 5 or 10x the computing power of the CG pro...). On the other hand, it is quite possible that the number of graphical bugs is much higher with a gamer CG (already with a pro CG it's a disaster).
For a limited budget like yours, a CG gamer with an i7 processor seems suitable to me (the equivalent with pro gear would cost 2 to 3x more). I wouldn't recommend a low-end pro workstation (probably more reliable, but it will have a much lower power than your home-built 'gamer' configuration).
If you don't want to overclock, avoid K processors (more expensive than models without overclock possibilities) and maybe switch to a higher range.
Do you have examples of prices 2 to 3 times cheaper?
My pro station cost 1700€ if you divide by 3, it's not even 600€. A game configuration for this price is not great...
Beware of benchmarks. What tests have been carried out?
I already think that Christophe must specify its use. Because there can be big differences depending on the network environment and the type of use. For example, visualization, opening of large assemblies of several thousand parts, simulation...
Pro cards are really very expensive, that's why I prefer to choose a gaming card. According to the information I had, the main difference is the realview which is not optimized on a gaming card, but I can do without it.
Would the i7 6700, 3.4 GHZ at €375 be a better choice than the i5 6600, 3.5Ghz at €300?
The i7 can't be overclocked, while the i5 can.
Where is it worth spending 440€ to get the i7 6700K 4GHZ?
My use will be for assemblies of 100 to 200 pieces at little ready. Some exceptions will exceed 500 pieces, but this will be rare. I have a network, but I prefer to leave the files on the hard drive as long as I work on them, I put them on the network when the project is finished.
SW only really uses the processor during the calculation phases.
If you use local files, I think you should increase the capacity of your SSD.
Beware of overclocking. I don't think that's the right track. Because it takes a lot of time for negligible gain and poses major stability problems. Not the best for work.
So a big CPU will be faster to perform calculations, but I would see a lot of difference when I go to visualize my assembly in 3D.
Currently, when I visualize an assembly of a hundred parts, I have a large block when I move my assembly, and then it redraws itself when it is fixed. My PC is not able to adjust the assembly in real time.
If I understand correctly, it's mainly the performance of the graphics card that is important for that.
The 6700 fits into my budget, it's a little more expensive than the 6600K. If overclocking is causing stability problems, in that case it would be better for me to choose the 6700 rather than the 6600K?
I don't think that the display of the movement in 3D is an option, it's more a problem of graphic power.
If I have a simple part it displays well, as soon as the assembly becomes complicated it's a disaster. I should point out that I have a very bad graphics card currently, it's a simple office PC.
The jerky display is mainly due to the power of your graphics card (and its optimization: this is the interest of pro cards which for the same (or almost the same) GPU give you 2 to 3x more images but for a price 3 to 4 times more expensive).
Until now, SW didn't really take advantage of the presence of many cores and it was better to have a dual high-frequency processor than a quad-core running 2 times slower. This has evolved a bit on the drawings where the rendering of the different views is done on several cores now.
32GB of ram seems huge to me, I have a machine with 8GB and I've never saturated the memory (I've never loaded a whole backhoe loader model either). Our models are in the range of 100-200 pieces max with simple external shapes (cylinders most of the time). Even my calculations with contact management under simulation go smoothly.
Here is an old bench comparing pro and non-pro graphics cards:
This may not be true anymore but the difference in performance was less felt at AMD (the gaming card has worse results but not much compared to the pro card). At Nvidia, you wonder if the gamer drivers are not deoptimized when they run a pro app.
Don't forget that a mid-range pro card costs the price of a station: a quadro K5000 costs around 1500€ for example. At this price you have a big gaming station with the top of the gaming video card.