Conceptronic CGIGA

Mine doesn't connect all PC's/Laptops with 1Gbps. Especially Realtek based NICs tend to be connected on 100Mbps (majory of cheap NICS is realtek based) ! My PC's only connects at 1Gbps when I power the Switch after booting up all PC's first! (All cables are 3 meters CAT6)
Conceptronics replaced the device (service is OK), but the replacement has the same issue! Gave up on on this piece of crap an bought a DLINK (DGS-1008D). With the DLINK my connection problems are gone and it consumes less power (more ports, but just 4 instead of 7 watts)