NEW YORK (MarketWatch) -- The dollar gained some steam early on Wednesday, as U.S. stock futures remained mostly lower even after a report showed orders for durable goods rose more than expected in July. The dollar index (DXY 78.48, +0.24, +0.31%) , which gauges the U.S. unit against a basket of six major currencies, stood at 78.541, up from 78.343 in early trade, and from 78.240 late Tuesday.