R710 PERC 6/i issues

I have an R710 server with a PERC 6/i controller.  It is currently used for video surveillance.  After a few days, I realized that more storage was needed to give us 3 weeks of historical, so I ordered (4) 1.2TB 10K drives and put them on their own Virtual Disk as a RAID5 (the primary virtual drive is a 4 disk RAID 5 with 600GB 15K's).  A few days after firing up the server and pointing the video surveillance software to the new drive D in Windows, the new virtual disk tanked and stopped recording video.  It showed a drive had failed, so I replaced it.  Then another drive failed and I replaced that.  It seemed to bounce around to different slots, no consistency.  At that point, I'm thinking it is the PERC controller.  I removed the virtual disk and pointing the video surveillance software back to drive C and everything was working fine again.  I took apart the server and reseated the riser card, the PERC card, the cable from the PERC card to the front where the drives connect.  I then created a new virtual drive and same result.  It all locked up again.  The drives were used, so there is that variable, though I ordered 6 and the 2 spares were 'failing' according to the amber blinking light on the drives (it's a video server, so shoestring budget here).  I am going to try another PERC card, but was wondering if anyone has any input on this.  I did upgrade the PERC firmware to the latest.