Dell Precision 3431

Dell's specs say Precision 3431 SFF supports either 200W or 260W PSU.

Can you tell us why you want to upgrade the PSU?

Instructions to replace PSU are here.

You'd need to know if a new PSU has the right power connectors for this motherboard, fits into the available space, mounting holes line up, etc, etc. 

You might contact Dell Spare Parts to see if the Dell 260W PSU is available and its cost.  In US: 1-800-357-3355. Have your Service Tag handy. (Don't post Service Tag here.)

Thank you for the response.  I'd like to install a MSI Radeon RX 6400 Areo ITX low profile gpu.  It does not require an external power hookup, runs off the pcie slot for power.  Just wanted to see if my SFF could handle it.

What's the recommended PSU size for that card? Will a 260W PSU even be big enough?

From pics in the Service Manual the long/narrow PSU in the 3431 is probably a Dell custom design. So an off-the-shelf (non-Dell) PSU may not fit and probably won't have the right connectors.  It's possible somebody like modDIY makes adapter cables that would work with a non-Dell PSU in your Precision.

You'd still have to find a PSU with the right wattage, that fits inside the SFF case, with matching mounting holes etc. Or consider mounting a new PSU outside the case...

Maybe somebody else has experience upgrading this PSU, but it sounds -to me- like a real DIY project...

The card pulls about 58W according to the website.  It requires not external power source.  I am able to fit a nvidia T1000 in the slot and get it to work.  that is a 48W card but doesn't quite cut it for the what I would like to use it for, VR experience.  I appreciate the help in this matter.

Looks like MSI recommends a 350W PSU for this card.

So even the 260W PSU may not be adequate. That much extra load on the 260W PSU could cause an early PSU failure, assuming it will even power everything if you install it.

Sounds like you should look for a different PC to meet your intended uses...

Also, compatible GPU's from the Precision 3431 Spec Sheet.pdf :

Hi @jjt2200,

I have experience answering GPU compatibility questions.  A 260w Dell PSU can easily handle 58w card.

Likewise, Dell 275w and 290w PSU's I have experience with in another forum can easily handle 75w cards, which is within Dell specs.

Mfrs. almost to have to boast total recommended PSU power because aftermarket PSU's often skimp on 3.3v/5v rails as compared to Dell.  Therefore, an aftermarket PSU that boasts more total power is often needed to get the required wattage on the 3.3v/5v rails.

@jjt2200,

Thanks for the kudos.  I also meant to say before "...required amps on the 3.3v/5v rails."