GPU With No External Power

[police101]

So I've been searching around on Google (there you go, I searched. So no critisizing saying I didn't try first!) and I have not found a solid answer and am getting mixed feelings. To set the record straight I figured I would seek advice.
I have a 220w power supply. Just buy reading that you may know that a graphics card is almost impossible to add to my computer. I thought about investing in a new power supply, but there is no professional ones available. I do have the option to buy a custom made power supply that is specifically built for my computer but I don't know if I want to risk my computer trying that. After some searching, I found that obviously some GPUs do not require an external power source and get power from the motherboard. My question is if I was to buy a graphics card, for example a GTX 750ti, would it be OK on my computer because the graphics card has no external power cord and my power supply is 220? Or would I still need a bigger power supply even though the card gets power through the motherboard? And would it be safe considering the minimum specs say 300w minimum or would I need to find a smaller card?
Thank you to anyone whom helps me with this question!

 

[renz496]

What is yor entire spec? 220 seems way too low though in PCPER test an OEM Pc with 250w PSU able to power the card just fine (still depending on other component).

 

[GChaioz]

Graphic cards don't get their power from the motherboard. You need to connect a PCI-E connector from the power supply and connect it to your graphics card to give it power.

 

[InvalidError]

220W MIGHT be enough depending on the output distribution between rails and quality of the PSU itself.

Buying a 400W PSU won't help you if you buy a junk-quality unit.

 

[InvalidError]

Graphic cards don't get their power from the motherboard.

GPUs that use less than 75W can be entirely powered by the motherboard. EVGA appears to be making at least two 750Ti models without PCIe power connectors: their plain 750Ti and their 750Ti SC. Pictures of the PCB show an unpopulated footprint where the only PCIe power connector should have been.