Turned on my new refurbished hp Compaq Pro 6300 and it looked and ran great--until 3rd day when 5 beeps at the start-up indicated a motherboard issue.  Contacted supplier/refurbisher StallionTek, and within an hour was contacted to solve problem.  Great Service, none better!Do need to return computer for replacement, but shipment paid by StallionTek with their FedEx label emailed to me.  I hope they are able to return the hard drive on which I had loaded paid Kaspersky security software and other work.  Will see how that works out and update this review later.