Z840 motherboard in a Z820

[SDH]

A first post from Bogieb17 was closed by a moderator earlier today, but it is a good question and not the best welcome to a first time poster on this forum.  He has a Z820 v1 (with the 2011 boot block date motherboard) and asked about upgrading that box with a Z840 motherboard rather than swapping in a used Z820 version 2 motherboard (with the 2013 boot block date noted in BIOS).

I wish it was that easy...... but these HP workstations are significantly custom engineered and built by HP for each major version.  Yes, you can easily take a version 2 Z820 motherboard and put it in the Z820 v1 case, and all the cables cross match perfectly.  The same is not true for doing that with a Z840 motherboard.  Same idea with the Z420/Z620 boxes and Z440/Z640 motherboards.  I have already looked closely at that and it also is a no-go.  Nice idea, but too much is changed.  The max I've done is turning an old xw4600 into a Z400, and that was not worth the effort.

Depending on what processor(s) your Z820 v1 has you may be able to upgrade just the one or two processors with ones that HP certified for the Z820 v1, and get a big speed boost.  Those processors have really come down in price on eBay, used, by now.  More expense and effort will go into getting a version 2 Z820 used motherboard and shifting up to faster memory, and faster v2 processor(s).  That is what I have been doing with our v1 Z620 workstations.... pretty big bang for the buck, and it is a pretty fast project to swap in the v2 motherboard.

[DGroves]

i have both z820 and z840 systems, and "SDH" is spot on in his observation that it's not worth the effort

can it be done? yes but the effort to do so is beyond the returns/benefit in doing so for most people

if you like to modd cases for a hobby, and have plenty of time an money/tools then yes it's a doable project but for most people the best answer is no.....

the major issue is that both cases have only stamped I/O in the rear instead of a replaceable I/O shield that most custom atx cases have  there are also some other areas that need minor metal modding

some of the z840 cables for the ram/cpu connections may be too short as they are in different spots on each model's board requiring you to extend the connections by cutting the connector(s) off and extending the wires and then re attaching the connector (cable extenders are not recommended for this!!)

the power supply between the z820/840 is however compatible according to the HP part numbers, so the chassis main wiring harness "should" be compatible but i'm not 100% sure on this

the cooling shroud and expansion shrouds are the same between both systems

the cpu coolers are also compatible