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XPS 8940, would it be possible to upgrade OEM PSU?
Hi,
I've just bought a XPS 8940 and I'm considering returning the pc if there is no way to upgrade the PSU.
I plan on having multiple disks (HDD, SSD, M.2) with 4 or 5 monitor, an i9 10k and and big GPU in there. Therefore, I'm worried about the little 500 watt PSU even if it is platinum.
In the past, I had a premade computer's PSU die on me because I had too much components and asked too much of a little 350 PSU. However, when it died, I had it replaced quickly as it was a standard PSU.
Would someone know if the following combo would work?
Combo :
- Modding the case cut off a larger hole and add some mount fixation to anchor a 2.5" PSU. The existing space between the motherboard and the PSU is exactly 2.5".
- Use the dell OptiPlex 24 pin to 6 pin adapter to power up the motherboard.
Usually motherboard are 24 pin, but this motherboard only has 6 pin - Put an SFX psu like this cooler master V750-SFX and use EPS 4+4 Pin to power up the CPU
It has the following connectors :1 x ATX 24 Pin
1 x EPS 4+4 Pin
1 x EPS 8 Pin
4 x PCI-e 6+2 Pin
8 x SATA
4 x Peripheral 4 Pin
The motherboard have two 4 pin power connections named ATX CPU1 and ATX CPU. I've read somewhere else in this community that this is also custom to the XPS 8940. Perhaps the EPS 4+4 could connect directly to both with no adapter needed?
If this combo work, I'm keeping it, if it doesn't, I'm returning it.
I'm a software guy and hardware isn't my thing.
Therefore, thank you very much to whoever can enlighten me regarding if this would work or not.
_______________________________________________________________________________________
PS: I've also considered mounting a second DELL OEM PSU on top of the existing one. It would barely fit sideway. However, this would obstruct the PCIe x4 connector so it isn't as good as the combo above.
redxps630
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December 30th, 2020 12:00
Afaik it has not been verified that 8940 proprietary 6 pin ATX power connector uses same pinout as the 6pin in some optiplex models. It is risky to experiment.
AXMIM
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December 30th, 2020 13:00
Ok, yes, indeed it is risky.
@redxps630 Do you know if the EPS 4+4 could plug into the ATX CPU1 and ATX CPU?
If the EPS 4+4 fit the CPU power atx plug, then I might ask a dell representative to determine if it is the same 6 pin layout or not.
If it doesn't fit, I won't bother asking them as it will be clear this computer is too much of an hassle to upgrade.
redxps630
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December 30th, 2020 16:00
EPS 4 pin 12V is likely the standard cpu power connector followed by 8940 (It is hard to imagine Dell would design a non 12V connector for CPU), but I would confirm it with Dell engineer help desk. Also look at Dell stock cpu connectors to verify there are two yellow and two black wires for the 4 pin connector that match standard EPS pin out (yellow for 12V and black for GND).
The problem is 4 pin connectors to different locations on board. The industry standard would be a single 8 pin or two 4 pin side by side.
redxps630
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February 11th, 2021 04:00
AXMIM
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February 11th, 2021 22:00
Thanks for the update @redxps630
Yes, I called the support and the tech I spoke with said layout was the same as other dell model.
However, I wasn't sure if he understood the question to begin with, so I couldn't rely on this info.
In spite of this, I kept the computer.
For now I'm safe, because the computer is still under warranty and I haven't added/replaced much components yet.
Before or right after the warranty runs out, I'll use an multimeter to check needed volts per pin and buy the above adapter if it is good. Otherwise, I'll DIY my own custom adapter (with some help of a friend if it's too hard on me). Honestly, I'm also hoping that by that time, an adapter for it will be available on the market.
With a working adapter ready at hand, if the PSU die, I'll be able to quickly get the system back up again by borrowing a PSU and run from it temporarily with the case open and psu outside the case. Therefore, I won't need to rush things out and/or wait for long shipping. From there, I'll check if I buy another dell PSU or go down the road of modding the case to mount an SFX psu in there using a dremel. Perhaps a 3D printer could do a nice socket to hold the SFX tight in place... I getting carried here....
My best scenario remains to never have to change it.
Anyway, thanks for the pinout, if I ever need to change it, I'll double check what the multimeter is telling with the information you provided to avoid mistake.
Regards