That noise on the white car (as most noticalbe) may be fixed without such big performance decrease, use scaling parameters for ssao/ssil:
SamplingQuality=0
SizeScale=0.75
SourceTexturesScale=0.75
or extreme quality of sampling, but even more blurred:
SamplingQuality=1
SizeScale=0.5
SourceTexturesScale=0.5
SizeScale - performance is most dependent from it, 0.75 is twice faster than 1.0, 0.5 is 1/4 of maximal quality 1.0 and so on. But, if i remember, values greater than 1.0 also supported (perhaps 2.0 is the limit) for SizeScale parameter and it will be very slow and detailed.
The same for antialiasing, AntialiasingUpScale parameter increase performance a lot, just set it 0.87 to get x1.5 times speedup and almost not visible loss of image detail (especially if to run at high resulitions like 1600*1200 and higher with 17-21" displays)