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xavierpita

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xavierpita

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April 21st, 2021 04:00

RTX3090 does not fit inside Precision 7920 Tower

Hi all

I'm getting a Precision 7920 Tower via the IT department of the company I work in. They also ordered an RTX3090 from a different vendor, that they should install before handing over the computer to me.

They now say that the current model of the RTX3090(GPU-NVRTX3090-24Z3) is too thick to fit inside the 7920 Tower. Seems odd....

Can anyone confirm this size incompatibility? 

 

Xavier

 

  • granjacob

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    Posted August 12th, 2026 03:39

    You can buy another side cover for a Dell Precision 7920 and cut it using a precision tool (a laser cutter would be ideal), leaving only the outer frame that fits into the chassis. In fact, you really only need to preserve the original mounting and locking mechanisms.


    Then, weld or attach a new panel to those mechanisms, extending it outward by about one to one and a half inches. And that's it! You'll have a custom extended side cover that provides the extra clearance needed to install larger GPUs inside the Dell Precision 7920.

    Dell should actually offer this type of extended side cover as an official accessory for these chassis. It would be a simple and practical way to give older Precision workstations enough clearance for modern, larger GPUs without requiring users to modify the chassis itself.

  • Oddssodds1

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    Posted August 12th, 2026 06:26

    More than one way

    (edited)

  • speedstep

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    Posted April 21st, 2021 05:00

    Its also too tall.

    The cover wont close.

    I dont find the beast not fitting to be odd at all.

    Its 3 slots wide and very fat.  On the airline you would need to buy 2 extra tickets.

    (\_/)
    (o.o)
    (___)O

    https://www.youtube.com/watch?v=cCI18qAoKq4

    You can see it will not physically fitYou can see it will not physically fit

  • speedstep

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    Posted April 21st, 2021 05:00

    It could work but not inside the case and power is an issue.

    https://www.amazon.com/dp/B06Y1SX7ZN/

    https://www.youtube.com/watch?v=bNelL7OJe4o

     

  • Andy812

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    Posted April 22nd, 2021 22:00

    Did you try unscrewing and removing the plastic and rubber push bar at the back side of the lock, on the inside of the cover?

     

    I had GTX 780ti which I tried inserting as an experiment. It would not fit there, but after removing the bar there is almost no difference with a standard full-tower ATX. The length should not be a concern since the said 780ti has 3 fans, it is long. (see the Gigabyte models on their website)

  • BlakeThoennes

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    Posted February 18th, 2022 22:00

    Hello all - I know this thread is old but...

    I have a 7920 tower. Still under warranty. Dual xeon gold cpus. Its got monstrous power supply and ability to support 2x 2080ti cards no problem.

    So why not 1x 3090? I got a founders edition card finally, already removed the metal support inside the case lid when I first put in the 2080ti, and have dual 8 pin power connectors.

    The 3090 is too long - so I removed the plastic fan shroud that couples the fans and front of case to the cpu/ram assembly shroud. So there is a small gap - not a huge deal since I run fans wide open there's plenty of air movement.

    The 3090 is too tall - So I bypassed the intrusion sensor (with a standard bic pen cap =-\) and the computer will power on without the lid fully closed now.

    However - I cannot get it to post. I am frustrated to finally have a 3090 - a gawd tier workstation with 56 cpu cores and not able to mash the two together no matter how many bypasses I try.

    Next is to try an external powersupply for the card to ensure its not a limitation there, and lastly an externally powered pci-e slot and a ribbon to the motherboards slot to subsidize power there.

    Since this is an issue that will take time that I don't have - I got an aurora Alienware R13... but the 3090 was backordered till late april - and I already have one. Hoping to make mine work with what space the case can provide (again anything goes to make it happen)... and will see about dell selling me one of their miniaturized 3090s when they restock late april.

    That's the official update on 3090FE and T7920 super computer.

     

  • BlakeThoennes

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    Posted February 19th, 2022 14:00

    Total LengthTotal LengthCard Touching Fan ShroudCard Touching Fan ShroudHeightHeightFanShroud RemovedFanShroud RemovedBicCap BypassBicCap BypassCard Installed and Powered OnCard Installed and Powered On

  • Andy812

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    Posted February 20th, 2022 16:00

    DELL boards often refuse replacing PCIe GPUs. You need to disable secure boot, and enable OS recovery counter. After a few cyclic boot failures it will put BIOS to some recovery mode, which will pick up the new GPU. Save the setup once, and it will boot up from that point normally.

  • BlakeThoennes

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    Posted February 21st, 2022 13:00

    Thank you Andy812 for your reply!

    I had honestly not even considered Secure Boot or Enabling OS Recovery Counter (not sure where this option is)! I know with Dell R910 Rack Servers there is a special jumper (not cmos or psw) that is necessary to clear a hardware error and cause the daughterboards to recalibrate.

    I had tried resetting bios and psw and looked for other jumpers on the 7920 to no avail. I tried different slots (cpu1) and different connectors. I figured it was a board draw/psu draw issue.

    I am going to replace this 7920 with the Alienware aurora 13 at my home and bench this 7920 at my office for further diagnostics. I am under warranty and will likely be filing a psu/mobo claim as the cpu1 pcie slot wont power a 2080ti (which it used to) and I had to move it to slot 2 on cpu0 (which is running successfully). 

    Since the 3090 did NOT WORK, I put a 3080ti in instead (also FoundersEdition) and it worked right away (again supporting potentially failing psu or weak board power). I will attempt the 3090 again with your suggestions in a few days when the A13 arrives to take over this units job as a home office pc. The 3090 will be attempted in that machine however I see Dell has a special model of 3090 that ships with it - so I suspect I will be disappointed further by lack of expandability and space.

  • Andy812

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    Posted February 21st, 2022 17:00

    Andy812_0-1645492531711.png

    I discovered it by accident. The manual says a bit different thing; but it appears, that it initiates some compatibility mode, which allows booting with a new GPU.

    Every time I was swapping GPU, I was waiting 3 cyclic reboots with this thing enabled, and then I was getting into BIOS setup. After saving the BIOS config everything was working fine.

    Secure boot should be disabled because it is a feature protecting the system from tampered hardware (remember True Lies, where Arnold attaches a hardware sniffer to a worksttion)