New video card to Z420 (Base Model ) work station

[uiblog]

Hi, I also have an HP Z420 workstation, but the power supply that is present inside has only the G1 cable and not the G2 that you see in the user's photo. The video card I would like to put on would be a Gigabyte 1070 G1 8GB gaming; I was wondering if it is possible to use an adapter from only 6pin I have (the G1 cable) to 1 8-pin connector? or do you say it would not work? thank you.

[BambiBoomZ]

Laobar,

The 2X 6 pin to 1X 8 pin adapter is not common. I had an MSI GTX 1070  that needs 1X 6 pin + 1X 8 pin- in a z620 and tried it in a z420. For that I used a 1X 6 pin to 1X 8 pin  + 1X 6 pin with no problems and had slightly above average performance.

Today I bought a GTX 1070 Ti (ASUS ROG Strix) that uses a single 8 pin.  I didn't want to try one 6-pin to 8-pin because the 1070 Ti uses 180W instead of the 150W of the 1070 so I looked for a 2X 6 pin to 1X 8 pin adapter. I was able to find only one 2X 6 pin to 1X 8 pin adapter anywhere. This is sold in the US but they will ship to Europe.

On Ebay DE:

https://www.ebay.de/sch/i.html?_odkw=https%3A%2F%2Fwww.ebay.co.uk%2Fitm%2FNEW-C2PCIE6T8-6-2-x-PCI-E-...

The link on Ebay UK is:

https://www.ebay.co.uk/itm/NEW-C2PCIE6T8-6-2-x-PCI-E-6-PIN-COMBINE-TO-1-x-PCIE-8-PIN-6-MADE-IN-USA/2...

By the way, one of the reasons I'm changing is that 2-fan MSI GTX 1070 is very wide and had to be squeezed into the z620 by smashing the power connectors as flat as possible.  It was not a good situation to have to press the access door shut. The z420 has a thinner access panel and was a still a tight fit, but not to the extreme of the z620. The 3-fan ASUS 1070 Ti is narrower and has the power connection set in a bit, so I expect that will be a much better fit. In another z420 I use a MSI GTX 660 Ti  (2X 6 pin) and that is quite wide as well, but does not press against the access panel. The message is  that, based on two samples, MSI GTX seem to be quite wide for zX20 series. I have seen the MSI width problem mentioned elsewhere also.

The z620 will then have a Quadro P2000 (which does not use an auxiliary power connector) plus the GTX 1070 Ti.

I would mention that the performance of the  P2000 in the z620 suffered substantially in Passmark benchmark using BIOS v. 3.92 - a loss of about 15-20%, and reverting to v. 3.91- quite difficult- restored it. That is however, going around the Spectre /Meltdown security.

BambiBoomZ 

[uiblog]

Hello, thank you for answering me, the problem is that I only have 1x PCI-E 6-pin cable in the power supply, so going to use one of those cables that you indicated, I should then find some other adapter from a sata power cord, go on 1x PCI-E 6-pin to connect the second PCI-E 6-pin cable that you indicated to me.

Or put an ATX aftermarket power supply (I would have a coolermaster v700 possibly available) and then go looking for a 24-pin adapter to the 18 pins present, if I remember correctly, in the motherboard.

What do you think about it? do you say it is feasible or could there be problems with operation? . Thanks in advance for a possible answer.

[BambiBoomZ]

uiblog,

I think attempting to adapt a new power supply to the z420 would be the most difficult option.  The problem is that HP does use a different main  motherboard connector and the output of each rail would need to be compatible.

Consider using a Molex 4-pin to PCIe 6-pin adapter, for example:

https://www.newegg.ca/Product/Product.aspx?Item=9SIAF6280Y9022&cm_re=Molex_4-pin_to_PCIe_6-pin-_-9SI...

I've forgotten the figure, but I think SATA power is limited -13A? whereas a Molex 4-pin supports 11A per pin and at 12V means it can provide 132W. It is possible to use 2X SATA power to 1X PCIe 8-pin:

https://www.newegg.ca/Product/Product.aspx?Item=N82E16812423200&cm_re=sata_power_to_pcie_6_pin-_-12-...

I use a Molex 4-pin to run an ASUS STX Essence soundcard in a z420, and that card uses quite a lot of power to run the preamp and also a 25W/CH headphone amplifier.

BambiBoomZ

[uiblog]

Hi,

In the end I took the following cables (hoping that everything works):

1x https://www.ebay.it/itm/253814001182

1x https://www.ebay.it/itm/NEW-C2PCIE6T8-6-2-x-PCI-E-6-PIN-COMBINE-TO-1-x-PCIE-8-PIN-6-MADE-IN-USA/2528...

I just hope everything works 🙂

[BambiBoomZ]

uiblog,

I think it should work.

Just to be absolutely certain:  I've never seen a z420 - I've had three, nor a z620 -had two that did not have two PCIe power leads for GPU's.  It is logical to have two as there are two x16 slots fro grpahics cards.  I remebered that when I first recived one of the z420's I could not find the second 6-pin wire I looked and looked until I relized that the connector was inside the lower front fan casing.  I thought it was the power for that fan. Ii know that sounds a bit silly, but this happened to me. Have one last look with a strong light for a wire that goes inside that lower front casing. Just a chance,...

BambiBoomZ

[SDH]

MtothaJ is correct.... you're worried about a non-issue.  ATX standard is 75W per PCIe 6-pin supplemental power cable.  HP workstations give more by quite a bit..... 18Amps x 12VDC = (you do the math).  nVidia is referring to a standard ATX power supply, not the HP workstation power supplies built to higher-than-ATX standards.

This is why HP sells their adapters we have posted about here that let you do things with their PCIe power cables you cannot do with an ATX-standard power supply's cable.

Just get a good adapter with all or almost all of the pin positions populated.  You don't need to only buy a HP one, just a good brand name one.  You'd be fine to use that Evga aggregator adapter M linked to, but you don't even need to use both of your Z420's 6-pin supplemental power cables for that.

[SDH]

Bambi.... you are thinking of your Z620s.  The black plastic front PCI fan casing has two receptacles for the two PCIe supplemental power cable plugs to fit into, doing nothing.  The black plastic front PCI fan casing for the Z420 has none of those receptacles.

The Z420 600W power supply has one of those PCIe supplemental power cables (18A x 12V = 216W capacity).  The Z420 400W power supply has zero of those cables.

I'm working on a Z420 v2 project that involves an 85.00 (including shipping (!)) brand new HP case with a brand new HP 400 W power supply.  I looked and looked and never found a 6-pin PCIe supplemental power cable coming out of that power supply.  I had it in my hands.....

The 600w power supplies for the Z420 are traditional HP quality; not so the 400W one (but I am on a lowest-cost project right now just for fun).

[BambiBoomZ]

SDH,

Yes, It wasn't clear. The second six pin connector was pushed into the slats of the front fan assembly:

https://www.ebay.com/itm/HP-647113-001-Z420-Workstation-Front-Cooling-Fan-Assembly/372283565284?hash...

>and I assumed that the cable was the front fan power connection.

And both 600W z420's have two six pin connectors. But, I see that the OP's z420 is a V1 and does not have the front fan.

You're correct that  the 400W power supply does not have an integral 6 pin. The 400W system had a single 6 pin, connected to the Molex 4-pin, but that may have been an added for an optional GPU or by the original user. Z420_3 was the only z420 purchased used.

While current GPU's are very efficient for power useage:

https://www.studio1productions.com/Articles/NVidia-GPU-Chart.htm

> it seems any workstation with two GPU slots would have some provision for supplemental power.

The evolution of GPU power efficiency is striking. Note in the chart that a GTX 480 and Titan XP both require a 600W power supply and a GTX 550 and GTX 1060 will run on a 400W.

BambiBoomZ

[uiblog]

I was still looking for the second 6pin PCIe cable but there is no track (on my HP Z420 workstation there is no fan on the front), so I think I have version 1 of the workstation. I just hope to solve using those 2 cables I bought.