Bear with me, I'm too lazy to go back and quote people here.
Samarkand was called by the Greeks during Alexander's time Marakanda, there is no doubt about this. The Greeks basically always attempted to produce foreign names accurately when giving names to places. Marakanda is the name that appears in the Greek texts and there's no reason to doubt its relative validity; it's not even remotely Greek sounding. I honestly cannot see how some of you can see more similarity between SemizKent and Samarkand than Marakanda and Samarkand. In addition, the Greeks reported Soghdians in the area (Alexander's generals had difficulty dealing with them and Bessos without Alexander helping), not Turks. The Sakae were the Scyths, the Scythian language, IIRC, is related to the Persian language.
The Greeks didn't consider non-Greeks to be barbarians, but non-Greek speakers. The word "barbaros" came about because all foreign languages sounded like to Greeks was "barbarbarbarbar." The Romans adopted this word. They, however, took an interesting turn with it. A "barbarus" could be merely a foreigner or stranger or uncivilized. Romans considered peoples that sported beards barbarians, which is where the Roman word for beard: barba. Ultimately, the English word "barber" is derived from barbarian
The Greeks considered the Persians to be descendents of Perseus, hence the corruption of Parsi/Farsi.