Windows 7 Pro 64-bit erractic performance after clean install

My small scientific consulting business runs on Ubuntu except for a few legacy applications that requires Windows.  I built two desktop PCs last Fall based on Intel i7-4770K processors and MSI CSM-B85M-P32 motherboards.  These are dual-boot Ubuntu 14.04.2 64-bit and Win XP Pro SP3 on one and Win 7 Pro 64-bit.  Both have 8 GB RAM and SSDs.  XP machine runs fine, Win 7 machine has been a disappointment.  I just did a clean install on a new Intel 730 series 480 GB SSD (previous brand X SSD failed).  Have same problems though with garbled audio and poor performance.  They seem to go together.  Performance monitor sometimes runs, bot most of the time it is "Not responding".  Also will not shutdown properly or complete all the updates.  Have run chkdsk /f c: but no errors.  Have done all the usual checks.  Win 7 drivers came from CD that came with motherboard as well as what Win may have downloaded.  Device manager does not show errors.  Do not think it is hardware problem as operation under Ubuntu is flawless.  Another factor is the VIPRE internet security, if installed, will not work.  Threat Track support has recommend another version of same software, but want to get issues resolved (have Windows defender in place) before trying VIPRE again.  I just got an hp dc5800 off-lease with Win 7 Pro 64-bit installed and VIPRE runs perfectly.

Where to start on troubleshooting?

Thank you,

John