Possible PSU and Case Issues for When Upgrading GPU

'ELLO!

(Before reading this, remember that I've not been doing much computer-related research/anything of that manner, so my terminology may be wonky)

ALSO! A 750ti might do the job as well, but maybe not for very long into the future.

So, after about four years, I've had enough of having a god awful graphics card, so I'm upgrading, and I'm pretty much decided on an RX 460. The main reasons being it doesn't require any 6 or 8 pin PCI-E power cables. But the question I've had on my mind is still power related. Or at least one of the questions is.

THE ACTUAL BLOODY QUESTIONS:

You see, the computer I've been using is a crappy prebuilt, with what I assume is a terrible Chinese PSU. I've been running a R7 240 for a while (if you're wondering why, check out the last paragraph/heading), and that has a very low TDP of 30 W. Meanwhile, the 460 has a 75 W TDP. I know TDP isn't entirely based off power consumption. There are two issues I see here: cooling and the PSU. And by the way, this is the 460 I'm looking at: https://www.newegg.com/global/au/Pr...814137028&cm_re=rx_460-_-14-137-028-_-Product

The RX 460 and the R7 240 only take power from the motherboard, not directly from the PSU, so would there be no issue here? I assume that if my PSU has the correct connectors to power an R7 240, it should be able to supply enough power for any GPU that does not require any external power cables. Is this the case?

Speaking of cases, the other issue, cooling, comes from the fact that my crappy prebuilt case has one fan mounting place. For a fan that is about 80mm. So, do you think there is any way in which an RX 460 could even run in my case? What if I find a GPU that's good enough for my needs with a blower style cooler - do you think the temperatures would be relatively fine then?

That's all the questions I have ATM, thanks in advance!

Q: Why do you have an R7 240!?

A: I was going to get a new GPU for the prebuilt (I think I was looking at a HD 7850 or something), but dad said "No, we'll need a new power supply", and decided I would buy the crappiest GPU ever. I got about a 10-ish FPS boost from the 10-ish FPS I was getting. And this was in 2013-ish. Ish. Ish. Ish. Etc.

 

I have an RX 460, and it takes all the power directly from the motherboard. I have applied a moderate OC, and it's still fine.
The case will run a bit hot, so get some better fans/more fans? If not possible, you need a new case.

 

It's not possible to get any more fans, and I doubt drilling and cutting holes in my case to install more fans is a brilliant idea, so yeah, maybe another case is in order.

 

What size MoBo do you have? If it's mATX or mITX, get the CoolerMaster N200 case. I have it, and it can have up to 6 fans (comes with 2), or 4 and a 240mm water cooler, aswell as good cable management. Finally, it's only 40 bucks!

 

I have a B85M PRO-3, so it's mATX. I'll look into that case, thanks!