I didn't understand any of what you just said.
I mean, from context I get that PSU is power supply, but I guess 300W is bad?
GPU is a graphics card, I'd guess?
I mean this must be what it's like when people start talking about movies in front of you.
Modern Graphics Processing Units (GPUs, i.e. "video cards") can require 300-350W power just by themselves. If you are looking to build a "gaming" computer, the usual recommendation for a Power Supply Unit (PSU) is going to be > 500W unless you are going to stick with the lower tier GPUs (ones which require no supplementary power or only one 6-pin
PCIe aux connector).
Well it doesn't suck, but it uses an Ivy Bridge processor (i5-
3xxx series) which is from 2012. If you were getting it to run WinXP- or Vista-era stuff it would be fantastic.
Different processors support different instruction set extensions (you might've seen things like SSE, SSE2, SSE3, SSSE3, SS4, AVX, AVX2) and the newer the game/OS, the more likely it is that game will require a processor that supports the newer instruction sets. Lack of SSSE3 support is what is finally spurring me to get a newer computer, because while the beta of Destiny 2 did not require SSSE3 support, the released game did,
which caused some trouble for those of us still using processors that predate SSSE3. Computer stuff usually runs on a 5-7 year cycle, and it's been 7 years since Ivy Bridge, so that's the reason behind my recommendation for Haswell (2013) or newer.
--Patrick