|"desktop its a acer aspire x1200-b1792a"|
"The Small Form Factor (SFF) case severely restricts the size & layout, plus you have a weak 220W power supply that cannot be easily upgraded due to it's size."
As in, it's small physical size. You may not be able to buy a replacement PS with more capacity, or if you can, your choices are probably limited.
If you installed a video card in a mboard slot, there are very few video chipsets that require so llttle power that your system having a a 220 watt PS would be okay
The mboard may not fully boot or not boot at all when you install a video card in a slot..