Replacing GTX 760 Ti with GTX 780 Ti in Alienware X51 R2

[nov21903]

OK so essentially my father is getting the GTX 1070 for his computer, and he said I could have his 780 Ti previously installed on his computer. I know this most likely won't work because of the insane amount of wattage the 780 takes up, but I wonder if there is any way to be able to fit it in. The power supply is of course the 330 watt external PSU.

Sadly buying a 970 or something similar that I know will fit into the computer is out of the picture.

 

[n0ns3ns3]

the only (practical) thing that you can do is:
open the case and measure the motherboard and it's mounting holes - check if it's ATX compatible (most probably it is).
If yes, you can get a computer case for 30-50$ and a PSU for 50-70$
Than move the internals of your computer to the new case with 780ti.
There is no option to fit a card with over 200w tdp into a computer with external power supply.

 

[nov21903]

the only (practical) thing that you can do is:
open the case and measure the motherboard and it's mounting holes - check if it's ATX compatible (most probably it is).
If yes, you can get a computer case for 30-50$ and a PSU for 50-70$
Than move the internals of your computer to the new case with 780ti.
There is no option to fit a card with over 200w tdp into a computer with external power supply.

The motherboard that the Alienware X51 R2 uses is a mITX motherboard. I don't know if I can even put a higher PSU because the motherboard might not like the extra wattage it's getting.

But lets get past that and say I am able to buy a new PSU and throw my components into a new case; motherboard and all? I believe there should be no problem with that since any case with mITX compatibility should be able to hold the motherboard fine, but I want to just make sure that something won't go wrong.


EDIT: OK so I just bought this case: https://www.amazon.com/Cooler-Master-Elite-130-Mini-ITX/dp/B00DRA4F06

And this Power supply: https://www.amazon.com/EVGA-Bronze-100-B1-0600-KR-Power-Supply/dp/B00EON40CS/ref=sr_1_1?s=pc&ie=UTF8&qid=1469499740&sr=1-1&keywords=EVGA+600B

I feel like this should work as the motherboard is mITX. The 780 Ti should be able to be powered by the PSU shouldn't it?

 

[n0ns3ns3]

mITX is good. you can build a very nice system.
You should not worry about "higher psu" as it is a power the PSU can provide, it does not push it A bigger problem is when PSU can not provide what components want.
Regarding the case, you are going to need a case with good airflow as 780 produces a lot of heat.
This one will defenitelly do the job: http://pcpartpicker.com/product/VH2rxr/fractal-design-case-fdcadefnanosbkw (there is a ~5$ cheaper version without window)
This one seems to be able to do the job: http://pcpartpicker.com/product/fGvRsY/thermaltake-case-ca1b800s1wn00
As a side note: there are mid a and full tower cases that have mounts for mITX mother board. They might cost less.

The PSU.
Ideal option: http://pcpartpicker.com/product/Rp8H99/corsair-power-supply-cp9020091na

Here are decent quality options that can migrate with you through couple of upgrades:
http://pcpartpicker.com/product/fZyFf7/seasonic-power-supply-s12ii520bronze
http://pcpartpicker.com/product/3hkwrH/corsair-power-supply-cp9020102na
http://pcpartpicker.com/product/bTnG3C/xfx-power-supply-p1500bxtfr