UltraNas6: Slow read/fast write after upgrade HD (2TB-->3TB)

Thank you for the information.
Yes, I had 4 x 2 TB HD's and now 4 x 3 TB HD's.
I have also applied the latest firmaware of my switch (shame on me that I didn't checked this before).

The volume status in frontview is OK. All green and no Errors/warnings.


Now I'm having the following situation:

- Copy from NAS to laptop --> 75 - 85 MB / s (Yes!!)
- Copy from Laptop to NAS --> 10 - 15 MB / s (Damn ...)

When I use a direct cable (cross-over) I have:

- Copy from NAS to laptop --> +/- 95 MB / s
- Copy from Laptop to NAS --> +/- 12.5 MB / s


I als tried to enable Flow Control on the switch (on the laptop it's enabled) and this is the result for a copy over the network

- Copy from NAS to laptop --> +/- 85 - 95 MB / s
- Copy from Laptop to NAS --> +/- 12.5 MB / s

Additional info:

- on the NAS writing cache for HD's are on
- on the NAS datajournals are off

If you have additional tips, they are welcome!