Logo

HP t620: Mods 

In December 2019 I heard from Jerzol from Poland who had added a SATA drive to his t620. You can read about that here.

In January 2021 I heard from Max from Italy who had added a VGA port to his t620 Plus. You can read about that here.

In February 2021 I heard from Pawel from Poland who had installed two 2.5" SATA drives into his t620. You can read about that here.

In May 2022 I heard from Evan from the US who had fitted a 2.5" SSD to his t620. You can read about that here.

In October 2023 I heard from Marco who had fitted a second ethernet interface to his t620. You can read about that here.


Adding a VGA port

Max had got hold of a t620 Plus to run pfsense. As part of his setup he uses a KVM switch to share his keyboard and screen across various bits of hardware. The KVM switch is fitted with VGA sockets. As mentioned on the hardware pages there is an onboard connector on the t620 for a factory-fit option to add a VGA socket in place of the serial port, so this seemed to be way forward for him.

The standard part

As luck would have it he found a vendor on eBay selling the necessary part ("removed from working equipment - more than 10 available"):

HP T620 Internal VGA Port Cable p/n 739843-001 - T620 + Plus Thin Client Parts

The vendor (rwlisiura) was in New Jersey, USA. The part was $29, but after adding shipping and duty the price was a heady $60 here in the UK - and a similar price in Italy. As I write this a t620 (admittedly less flash and RAM) can be had on eBay.uk for $45.

However the vendor had included some excellent pictures of the part which enabled Max to work out the connections and then wire up his own VGA port.

VGA internal cable for HP t620
The standard HP part.

The Bits

Putting one together is straightforward. Max assembled:

  • A VGA socket.
  • A short length of ribbon cable.
  • A connector to match the socket on the board.

The 15-pin VGA socket is readily available. You may well have a scrap one lying around as Max did.

Ditto for the ribbon cable. I have a boxful of old IDE cables from ancient computers. The 40-way cables may be better to use rather than the later 80-way cables.

Max split the ribbon cable down to 13 wires. Standard grey flat ribbon cables always come with one edge marked in red to aid correct orientation. If you're using an offcut from a wider cable which has no such marking I suggest you run a red marker pen down one side to re-create the red stripe. In the diagrams below the individual wires are numbered 1-13 across the cable with '1' being the wire with the red stripe.

The 8 X 2 socket on the board has connectors on a 2mm pitch. It just so happened that Max had a number of suitable 8 x 1 strips to hand and so used two of these for his connector. In the UK Farnell stock suitable connectors (eg part M22-7140842) for ~£2. These 2mm board-to-board and board-to-cable connectors are made by Harwin and are available from other suppliers such as Mouser.

hp t620 VGA board connections Note the connector used by Max and the one whose part number is given above are sold as 'board mounting'. They work equally well as a plug on the end of a ribbon cable in these fit-and-forget circumstances. (You could add some heat shrink sleeving over the soldered connections if you want).

The connections

hp t620 VGA board connections

Starting with the VGA connector on the motherboard this is how Max wired up that end of the ribbon cable to his plug. The three pin positions marked by 'X's are not connected.

hp t620 VGA socket connections

The VGA connector viewed from the rear. The numbers given are those of the wires in the ribbon cable. The rows go:

 1, 3, 5, -, 12
2, 4, 6, 10, 8
 -, 7, 9, 11, 13

The Result

hp t620 VGA socket connections
Max's cable ready for installation.

hp t620 VGA socket connections
The VGA socket and cable in place.

 


Any comments? email me. Added January 2021