Optiplex 790sff power supply upgrade

easy upgrade to 280W.

https://www.dell.com/community/Optiplex-Desktops/upgrade-of-Optiplex-SFF-psu-to-280W-for-GTX1050-1050Ti/m-p/7536972#M40953

I think your 790 sff probably looks like this one https://cdn11.bigcommerce.com/s-h47f2g/images/stencil/500x659/products/7611/20332/1463099__50326.1517438039.jpg?c=2

and the sff in the video was optiplex 780 sff that looks like https://www.speedhelp.net/Bilder/Computer/P4/Dell/dell_op_780_sff/dell_optiplex_780_sff_4.jpg

yes there is a big change from 780 to 790 because the former uses BTX format motherboard and the latter ATX.  790 sff also uses standard ATX 24 pin.  

can you measure and send your sff psu physical dimensions?

Thank you for the response but unfortunately my power supply does not look like the one in the video. Mine is a long rectangle that is a 240w not a 235w if you can find another video or link for me that would be great! 

Hi @Dragon272, What GPU did you get?

Hi @redxps630, I couldn't immediately pull up dimensions on it, but might the Dell Vostro SFF 400w PSU also fit?

Hi thank you for being so kind, here is the dimensions of my psu 10.9 x 4.2 x 3.5 inches. Thank you so much for helping me.

Also I am am almost positive this is the psu that is in my optiplex 790 sff

https://www.amazon.com/Dell-Optiplex-desktop-H240AS-00-Computer/dp/B00ZR54C48

Hi I got a  MSI GT 1030 2GD4 LP OC Computer Graphics Cards. Thanks for all the help!

Wait..so is it fine for me to put that graphics card into a 240w battery? If so thank you so much for helping me. YOu are an amazing person!

there are Dell XE series psu that are long and look like the 790sff but they use proprietary 8 pin ATX connector, so can not be used in 790 sff.

the vostro 400W one physically will fit but can not be fastened to chassis so it will float inside.  similar psu dimensions are 3.4x2.5 inch. https://images-na.ssl-images-amazon.com/images/I/51yxcla9pZL._AC_.jpg

on the other hand I find some dell sff 275 w psu that may fit the 790 sff case, but it is only a modest enhancement of power.

Thanks for the compliment and accepting my post as a solution.  For further confirmation, you'll see that the GTX 1050 Ti has also been working in SFF models.  Optiplex 9020 SFF + GTX 1050 + YouTube  Granted the PSU in a 9020 SFF might not be the same exact wattage, it's pretty close.

the 24 to 8 pin is for people who want 8 pin ATX to deal with Dell motherboard.

the reverse would not work afaik.  the 8 pinout has no 3.3 V in it.  I am not certain one can adapt 8 pin back to 24 pin to power the 790 sff motherboard but you never know.  as to whether motherboard really needs 3.3 or not, idk.  the only other 3.3 v is in sata power.

Hi again @redxps630,

Worth checking out?  I've also seen it used on YouTube.  I think it might make the XE2 SFF 315w PSU adaptable to SFF models with 24-pin connector if I saw that right.  https://www.ebay.com/sch/i.html?_nkw=8+pin+to+24+pin+adapter&_trksid=p2380057.m4084.l1313.TR2.TRC1.A0.H0.X8+pin+to+24+pin+adapter.TRS0 

Also, thanks for the info.

XE: mini-ATX 24 pin

XE2: 8 pin ATX

XE3: 6 pin ATX

So if I have this staight - Can't go from 8-pin on the psu to 24-pin MB, but can go from 24-pin on the PSU to 8-pin MB.  The latter is the way I think I saw it on YouTube, as that particular YouTuber likes to deal with upgrading 7020's and 9020's, but not the XX10's.

I wondered if that was too good to be true - XE2 SFF PSU in SFF models with 24-pin MB.  If it were possible, seems like it would've been discovered earlier.