Hi all, I hope I am in the right news group. If not please point me to a place where someone can give me an advice in which direction I could look for an answer. I've been using the below mentioned board (see dmidecode) with the below mentioned SAS controllers (see lspci) for many years with normal (rotating/spinning) disk drives. I now bought 2 SSD disks to replace 2 of the spinning once and I was surprised to find out that the older disks are using 3Gb/s transfer rate while the SSDs are using 1.5Gb/s. The SSDs are reporting SATA 3.3 (see below) In the mptsas driver I see 3 and 6 but no 3.3 or similar. https://github.com/torvalds/linux/blob/ae545c3283dc673f7e748065efa46ba95f678ef2/drivers/message/fusion/mptsas.c#L3087C1-L3111C3 If I understand correctly the rate is negotiated by the controller and the mobo. I am wondering where could be the problem. Is it really matter of negotiation i.e. the driver does not understand 3.3 or a technical constrains/incompatibility at 3Gb/s? Last question: If I would have to replace the controllers, what controller would be recommended? Thank you in advance BR # lspci 01:00.0 SCSI storage controller: Broadcom / LSI SAS1068E PCI-Express Fusion-MPT SAS (rev 08) 08:00.0 SCSI storage controller: Broadcom / LSI SAS1068E PCI-Express Fusion-MPT SAS (rev 08) # dmidecode Handle 0x0002, DMI type 2, 15 bytes Base Board Information Manufacturer: ASUSTeK COMPUTER INC. Product Name: M5A97 EVO R2.0 Version: Rev 1.xx Handle 0x0028, DMI type 9, 17 bytes System Slot Information Designation: PCIEX16_2 Type: x16 PCI Express Current Usage: Available Length: Short ID: 3 Characteristics: 3.3 V is provided Opening is shared PME signal is supported Bus Address: 0000:00:1c.5 # smartctl === START OF INFORMATION SECTION === Model Family: WD Blue / Red / Green SSDs Device Model: WDC WDS200T1R0A-68A4W0 ... Firmware Version: 411010WR User Capacity: 2,000,398,934,016 bytes [2.00 TB] Sector Size: 512 bytes logical/physical Rotation Rate: Solid State Device Form Factor: 2.5 inches TRIM Command: Available, deterministic, zeroed Device is: In smartctl database [for details use: -P show] ATA Version is: ACS-4 T13/BSR INCITS 529 revision 5 SATA Version is: SATA 3.3, 6.0 Gb/s (current: 1.5 Gb/s) <<<<<<<<<<<< HERE Local Time is: Sun Aug 13 10:38:11 2023 CEST SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF INFORMATION SECTION === Model Family: Western Digital Red Device Model: WDC WD20EFRX-68EUZN0 ... Firmware Version: 82.00A82 User Capacity: 2,000,398,934,016 bytes [2.00 TB] Sector Sizes: 512 bytes logical, 4096 bytes physical Rotation Rate: 5400 rpm Device is: In smartctl database [for details use: -P show] ATA Version is: ACS-2 (minor revision not indicated) SATA Version is: SATA 3.0, 6.0 Gb/s (current: 3.0 Gb/s) <<<<<<<<<<<< HERE Local Time is: Sun Aug 13 10:38:11 2023 CEST SMART support is: Available - device has SMART capability. SMART support is: Enabled -- FCD6 3719 0FFB F1BF 38EA 4727 5348 5F1F DCFE BCB0