Adding a drive to a Z420

[gdwinco]

I have a Z420 with two drives (SSD and 2TB) connected to the SATA AHCI ports (0,1) on the motherboard. I would like to add another 3TB SATA drive. The SCSI daisy chain connector is there on the internal side and on the front side. 

Attached picture from HP site ~ similiar to my mother board - although the diagram on the inside cover of my box shows the speed of all drives as 3Gb/s. The  two SATA AHCI-3GB on the RHS are also there, 1 is occupied by the DVD drive, one open.

What is the difference between the SATA SCU and SATA AHCI connectors?

Can I just connect the new drive to the SATA SCU? or is it better to use the open AHCI connector?

What is the HP Part number I need to order for the SATA SCU to drive cable?

Thanks, Glen

[Dan_WGBU]

The Intel C602 chipset on the Z420 has 2 separate SATA drive controllers.  One is called an AHCI port, the other an SCU port. 

   - The AHCI controller has 2 6Gb/s ports, (ports 0 and 1), which are the gray connectors at the corner of the motherboard.  The 2 black right angle SATA ports are other AHCI ports that run at 3Gb/s.

   - The SCU ports are the 4 white ports at the bottom of the board.  All these ports run at 3Gb/s. 

The HP documentation you showed is (unfortunately) incorrect.  The picture shows a prototype Z420 board, and there were changes to the Intel C602 chipset before the Z420 was released.  The Z420 has only 2 6Gb/s ports on the motherboard, the rest are all 3GB/s. 

It is OK to connect the new drive to any of the white SCU ports.  The drive will also run if one plugs them into the black AHCI ports.  There are separate drivers for the AHCI and SCU controllers.  They should be installed already, and show up under Device Manager. 

I do not know the HP part number for the drive cable, but any SATA data cable should work. 

Caveat:  I have not personally tested all these configurations. 

[PatRyan]

My Z420 (LJ449AV) has a 128GB SSD 1st Drive and a 1TB HDD 2nd drive.  I want to gain more capacity for Windows and iPhone backups.  I am purchasing a 500gb Crucial MX200.  I would like to add it as an additional drive, but boot off of it by cloning my current C: drive to it.  That would let me use the original 128gb sst as a spare drive.

Will I have enough SATAiii connectors available for both?

How will I change things to boot off the new drive?

Or will I need to add the new ssd, clone to it, and then swap the two ssd drives?

Thanks