I'm a user of Solidworks user, along with Autodesk Building Suite, Sketchup, Wolfram, and Adobe CS6.
Given the budget and the demands of Solidworks- which needs both a strong single-threaded CPU performance, more or less requires a Quadro, and has one of the few really well-threaded rendering programs, my suggestion is to buy and upgrade a used workstation. This has several advantages: workstations are purpose deigned for high performance in these uses and are quiet, and as reliable, and have a strong support from the original maker. Very importantly, you don't have to build it, only plug in the upgraded CPU, RAM, GPU, and drives as you find them.
I did this with an HP z620, purchased to replace the analysis /simulation /rendering system, a Dell Precision T5500:
Dell Precision T5500 (2011) (Revised) > 2X Xeon X5680 (6-core @ 3.33 / 3.6GHz), 48GB DDR3 1333 ECC Reg. > Quadro K2200 (4GB ) > PERC H310 / Samsung 840 250GB + WD RE4 Enterprise 1TB > M-Audio 192 sound card > Logitech z313 > 875W PSU > Windows 7 Professional 64> HP 2711x (27", 1920 X 1080)
[ Passmark system rating = 3844 > CPU = 15047 / 2D= 662 / 3D= 3550 / Mem= 1785 / Disk= 2649] (12.30.15)
Purchased for $270:
HP z620 (Original) Xeon E5-1620 4-core @ 3.6 /3.8GHz) / 8GB (1X 8GB DDR3-1333) / AMD Firepro V5900 (2GB) / Seagate Barracuda 750GB + Samsung 500GB + WD 500GB
[ Passmark System Rating= 2408 / CPU= 8361 / 2D= 846 / 3D = 1613 / Mem =1584 / Disk = 574 ] 7.13.16
Purchased:
CPU's: $152 + $154 (used)
CPU riser: $150 (used)
RAM: $128 (used)
GPU: $260 +86 (used)
Drives: $150 + 82 + $65 (new)
Sound card: $36
Set of all case plastic parts: $56
TOTAL= about $1,600
I can recover a bit of the cost by selling the original E5-1620 (about $70) and the Firepro V5900 (about $70)
Result:
Analysis / Simulation / Rendering:
HP z620 (2012) (Rev 3) 2X Xeon E5-2690 (8-core @ 2.9 / 3.8GHz) / 64GB DDR3-1600 ECC reg) / Quadro K2200 (4GB) + Tesla M2090 (6GB) / HP Z Turbo Drive (256GB) + Samsung 850 Evo 250GB + Seagate Constellation ES.3 (1TB) / Creative Sound Blaster X-Fi Titanium PCIe sound card / 800W / Windows 7 Professional 64-bit > Logitech z313 2.1 speakers > HP 2711x (27" 1980 X 1080)
[ Passmark System Rating= 5675 / CPU= 22625 / 2D= 815 / 3D = 3580 / Mem = 2522 / Disk = 12640 ] 9.25.16
[ Cinebench R15: OpenGL= 119.23 fps / CPU = 2209 cb / Single core 130 cb / MP Ratio 16.84x] 10.31.16
> which currently has the highest system rating of 249 systems tested on Passmark.
An example:
HP Z620 Workstation 2x Xeon E5-2603 1.8GHz 8GB 250GB Win 7 Pro 1 Yr Wty > $435
Add to that system:
2X Xeon E5-2690 8C @ 2.9 / 3.8Ghz: about $175 each
64GB DDR3-1600 ECC registered: about $140
Quadro M4000: used about $650
Samsung 850 Evo 500GB: $175
Seagate ES.3 Constellation 2TB: $140
___________________
TOTAL= about $1,890
It's worth trying to find a z620 with a bootblock date of 6.13, the system can use Xeon E5-2600 v2 series CPU's and DDR2-1866 RAM and the E5 v2's are generally faster with better single-threaded rates. However, the E5-2690 has the highest single-thread rating of first series Xeon E5-2600's. The Xeon E5-2687w v2 (8C @ 3.4 /4.0GHz) is better, at 2052, although these are still selling for $800-$1,000 each). If you found a used system that could use E5-v2 though, it might be worth stretching to a single E5-2687w v2 as the 3D modeling will be noticeably faster and a better gaming capability.
The E5-2690 is a very good combination of core /thread count and the turbo speed of 3.8GHz provides a good Passmark single thread rating of
1877. The Passmark calculation cycles rate of the z620 I upgraded of
22625 is also very good. comparing to an E5-2640 v3 (8C @ 2.6 /3.4, 2016, $950 each), produces a CPU rating of 21579 and single-threaded of
1733, so the E5-2690 is making contemporary performance for $1,200 less. compare also to modern CPU such as the i7-6700K (4C@4.0 /4.2GHz). The single thread rating is in the top tier-
2348, but the CPU mark of 11105 and having 8 threads for rendering instead of 32 means rendering times significantly longer.
Other systems to consider: HP z820, Dell Precision T5600, T7600, T7610 (can use E5-2600 v2)
I've had two HP z420's and the z620, and along with the Dell Precisions: 390, T3500, T5400, and T5500, all the used workstations I've had since 2009 have been 100% reliable, not a single component failure nor loss of data.
Cheers,
BambiBoom