I have a Highpoint RocketRaid 4320 adapter with a RAID5 array on a Windows Server 2008 R2 x64 system. The array was originally made with 3 Seagate 2 TB drives in 2010 or 2011. The array was later expanded twice with one drive (also Seagates). So there was then 5 drives in the array (and still is). Then one of the Seagates began to show errors in SMART and it was replaced with a WD Green 2 TB drive. One by one the other Seagates have also shown errors in SMART and they've been replaced with WD Greens.
The exchanges have gone through perfectly except the latest one a few weeks ago. The latest array rebuild took 14 days! It has taken 2-3 days before. The array was also extremely slow with transfer speeds after the rebuild.
I've searched the net and I've tried and checked the few things that have come up. Today I took out each drive one at a time and I connected it to another computer and ran WD Data Lifeguard Diagnostic on it. All the drives passed the Quick Tests -- i.e. no surface scan. I then booted up the server and right away ran a benchmark which actually showed pretty decent results (see file attachments). I don't think the array has ever been much faster than that. I waited for a few hours and ran the benchmark for a second and again later for a third time. The results are not so good anymore, but still much better then what they've lately been.
I read a blog post about interference in cables. Could that be the cause for the slowness? But why now? Why hasn't it bothered before? The fan-out cables are quite expensive -- as I probably should avoid the cheapest ones so I don't again end up with shitty cables -- so I wouldn't want to buy them for nothing.
The RR4320 has 2x 4 ports. The drives are currently connected 4 on the first port and 1 on the second. Would it be better to have them 3+2 or 2+3? Can I move the drives around without f'ing up the array?