The SPX futures test a critical area of support at the 20-day SMA, says Kevin Green. He tells investors to watch Tuesday's tech weakness, especially in Microsoft (MSFT) and Nvidia (NVDA), to see if traders buy the dip. KG's skeptical on the partial government shutdown and arguments that it will offer a bullish lift similar to last year's shutdown. On the earnings front, KG tells investors to watch Enphase Energy (ENPH) as call activity powers momentum.