PSU won't fit in case?

[_Froyo]

So recently someone on craigslist in my area was selling their EVGA 650 GS. It's a fully-modular, 650w PSU with 80 plus gold efficiency. He had only been using for a little over a year and was selling it for just twenty bucks, so I jumped on the offer. One small problem though: I don't think it fits in my case.

The plastic part of the lock mechanism for the side panel is just barely stopping me from getting it in. I'm trying to put this in my Optiplex 790 so I can upgrade my graphics card, but this little thing is in the way.

Here it is next to the stock power supply. It's ever so slightly longer, but otherwise the dimensions are exactly the same.

 

From what I've read, the Optiplex 790 supports standard ATX power supplies, which I believe the 650 GS is. I've seen multiple videos of other people upgrading the PSU of an optiplex 790, so what's going on here? Is the 650 GS just too big, and if so, should I try cutting off part of the plastic on the lock mechanism to fit it in? Or is this supposed to work fine and I'm just an idiot?

[Streetguru]

3 minutes ago, _Froyo said:

 

Just run it outside of the case, use double sided tape to secure it to the top of the case.

[Canada EH]

6 minutes ago, Streetguru said:

Just run it outside of the case, use double sided tape to secure it to the top of the case.

or zipties would work too. Cant really tell from the pictures, but it looks like some metal is in the way, can you cut the metal away?

 

First pic, has the slide in rail on left and the case "L" on the right. Cut them out, or bend them back. Then the psu may still lay on the mobo in which you just have it standoff a bit, no big deal.

 

Its a touch longer but how much wider is new compared to stock?

[BlueChinchillaEatingDorito]

When installing PSUs, it's sometimes better to remove the motherboard as the board and heatsinks will get in the way.

[0x1e]

I would remove what ever is in the computer and try again.

[_Froyo]

2 hours ago, BlueChinchillaEatingDorito said:

When installing PSUs, it's sometimes better to remove the motherboard as the board and heatsinks will get in the way.

It worked! After removing the board and doing a bit of fiddling with the lock mechanism (no modifications), the new PSU fit in just fine. Thanks for your help!

[buzzlightyear12345678]

What do I do here my psu really small?