The slightly good news regarding PC shipments in Q2 2016 could turn into actual good news moving forward according to International Data Corporation (IDC).The company reported that worldwide PC shipments of 62.4 million units in the second quarter this year showed a year-on-year decline of just 4.5%. Analysts had expected a decline of 7.4%, making the Q2 results better by 3%.Related: BREXIT ONLY PARTLY BEHIND SOME LOSERS AND WINNERSEnd Of Free Windows UpgradesWith Microsoft Corp. (NASDAQ:MSFTC) ending its free Windows 10 upgrade program July 29, IDC says the net result could be a boost in PC shipments in the second half of 2016.This is based on IDC’s theory that instead of paying to upgrade existing PCs, buyers, including companies, may decide to purchase new Windows 10 PCs.Original Projections Could ChangeIDC Vice President, Loren Loverde told PC World, “The PC market continues to struggle as we wait for replacements to accelerate, along with some return of spending from phones, tablets and other IT.”Overall, IDC has been projecting that year-over-year worldwide PC shipments would decline until 2018. A boost from Windows 10 PC sales, however, could push the 2018 date forward.Brexit Weighs InThat said, other factors such as the recent Brexit vote in the U.K. could have an impact that is not as yet known.Other voices suggest the cost of a paid upgrade, likely less than $120, would not be sufficient to cause individuals and companies to buy whole new computer systems. Those same voices caution that fear of bugs in Windows 10 will keep more away from an upgrade than the cost factor will attract.Related: WOOTRADER WEB TRAFFIC DATACompanies Watching For A SignMeanwhile, as Microsoft prepares to shut the door on free Windows upgrades, companies affected by PC (and related hardware) sales are watching to see which direction the buying public moves.At the top of the list, Microsoft Corp., may be looking for a win either way. That could be through additional sales of Windows 10 software or sales of Windows 10 Pro driven Microsoft Surface tablets.Others, including Hewlett-Packard Co. (NYSE:HPQC) and Sony Corp. (NYSE:SNEC) stand to gain if, as predicted by IDC, individuals and corporations elect to buy new hardware designed to make better use of Windows 10 features – especially after the expected Aug. 2, Windows 10 Anniversary Update.Finally, companies like Canon Inc. (NYSE:CAJC) and Seagate Technology PLC (NASDAQ:STXC), which supply peripherals and other hardware for PCs would be happy to ride increased PC sales coattails to additional revenue and greater profits into the end of 2016 and beyond.