What need to change for the Z840 to support a 16pin RTX4070ti ?

[KahF]

Hi, Have read some threads that the 1125W PSU can support up to 2 x300W GPU, I plan to acquire a RTX4090 which has 1x16 pin connector, can I just get 2x6pin to 8 pin adapter and use it as a 16pin connector ? The card will come with a PCIe5 12VHPWR Adapter. I am concern the pin layout of the RTX vs the 6pin to 8pin adapter. Any suggestion would be much appreciated.

After looking into the spec of the RTX4090, I am worried about the form factor size which is 3 slot and about 337mm/13.3inches length, can Z840 take it ?

[Prométhée]

hi

compare with the type of card that is possible with this model
open, measure/check
but actually, from what I have already seen, this type of graphics card does not fit in many computers!
moreover you risk overheating, if it is too tight, and poorly ventilated

https://support.hp.com/us-en/product/hp-z840-workstation/6978842/document/c04505606

HP Z440, Z640, and Z840 Workstation Series - Maintenance and Service Guide

also see if this can help you

Site preparation guide HP Z800 Workstation 1110 W power supply HP Z820 Workstation 1125 W power supp...

but, i found this, sorry in french

https://www.tomshardware.fr/la-geforce-rtx-4090-peut-desormais-occuper-un-slot/

Beyond its value, the GeForce RTX 4090 also impresses with its size: the Founders Edition version occupies three slots, some custom models downright four. After the escalation of power and size, like the Asus TUF RTX 4090 OC, a 34.5 x 13.5 cm monster weighing 2.4 kg, the period seems more like attempts to miniaturize the flagship of NVIDIA's GeForce Ada Lovelace line. Thus, after a small GeForce RTX 4090 blower, make way for an even more compact solution, occupying only a single PCIe slot.

[DGroves]

i've commented on this question numerous times, use the forums "SEARCH" feature to read them and other replies on this subject from other users The RTX 4070 Ti can pull up to 285 watts, 35 less than the RTX 4080.

and a quick bit of information...................... the stock 850 watt supply will not support the power draw of this card.

Up to one 150 W or two 75 W graphics cards with 850 W power supply

the optional 1125 watt unit can support Up to two 300 W  graphics cards with the  optional 1125 W power supply (other configuration restrictions may be required)

read on to see how to do a quick check that works on any system 

a good rule of thumb is to look at the HP "quickspecs" on the z840 and note the HP approved video card options which are listed

select the lowest card (highest performing model) in the list,  then google that card models wattage

use that figure as a reference and compare to the card model you want and if the wattage is under the HP number your ok to use your model

if your card draws 20 watts more than the HP figure i would not install it

the HP z840 service manual also covers how many video cards can be installed and the total HP approved wattage

since the HP power supply is not a single rail design like most consumer power supplies nowadays (it's a multirail design) you must stay within the HP z840's power supply's listed GPU rail wattage (for either supply)  which is

https://support.hp.com/us-en/document/c04505606

nvidia posts the specs on their website:

https://www.nvidia.com/en-us/geforce/graphics-cards/40-series/rtx-4070ti/

https://support.hp.com/ph-en/product/hp-z840-workstation/6978842/model/6978844/manuals

[Prométhée]

---

@KahF wrote:

Hi, Have read some threads that the 1125W PSU can support up to 2 x300W GPU, I plan to acquire a RTX4090 which has 1x16 pin connector, can I just get 2x6pin to 8 pin adapter and use it as a 16pin connector ? The card will come with a PCIe5 12VHPWR Adapter. I am concern the pin layout of the RTX vs the 6pin to 8pin adapter. Any suggestion would be much appreciated.

After looking into the spec of the RTX4090, I am worried about the form factor size which is 3 slot and about 337mm/13.3inches length, can Z840 take it ?

---

thanks @DGroves  personally I answered the question in the subject, not in the title, rtx 4090 and rtx4070ti being different

[KahF]

Hi Prométhée, Thank you for pointing out the risk of overheating, I do agree that the RTX4090 may push the Z840 beyond the limit, since they are born in different era 😄

Now, I may have to make a decision if to look for a Z8 G4 instead of Z840 to see if the Z8 can support RTX4090, or I have to use an older card like RTX3090 on the Z840. 

Have a great weekend.

[KahF]

Thank you DGroves for the info link.

[Prométhée]

I haven't looked, but you'll have to check
except if, as I have seen, it would be possible to find graphics cards in a smaller format, you must have a relatively spacious case, and always the problem of additional connectors
unless it is offered with these computer models?
Thanks, Have a nice week end @KahF 

https://www.nvidia.com/en-us/geforce/graphics-cards/40-series/

https://www.nvidia.com/en-us/geforce/graphics-cards/40-series/rtx-4090/

https://www.nvidia.com/en-us/geforce/graphics-cards/40-series/rtx-4090/#system-compatibility

[jessquirl]

I put my RTX 4080 (exact same size as an RTX 4090) into my Z840. Fits fine, no overheating. I do however have limited frame rates max of 60fps on medium setting on Flight sim 2020. Not the earth shattering world I was promised. I am in the process of returning it. I have no difference than my GTX 1080 Ti I was replacing. ;( SUPER DISSAPOINTING FOR $1,200 for sure.

[KahF]

Thank you @Jessquiri for your reply. It is good to know the size of RTX4080 can fit into Z840. I m sorry to know that the RTX4080 not able to perform as you expected, would it be the power issue or it is the RTX4080 not powerful enuf ? Hope you can get one that can fit your expectation soon.