Distorted_doggo

its really up to you. for the computers i build i always buy used. as long as you buy from a reputable seller you should be good. here’s a few examples all with sellers over 99% positive feedback
 
1070
https://www.ebay.com/itm/155350578230?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=2bCBlDMmSmy&sssrc=2349624&ssuid=ZqvfcQYkSbC&var=&widget_ver=artemis&media=COPY
 
1080
https://www.ebay.com/itm/325364269767?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=Bur8NZm3S4y&sssrc=2349624&ssuid=ZqvfcQYkSbC&var=&widget_ver=artemis&media=COPY
 
1080ti
https://www.ebay.com/itm/165909653034?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=i8UdcXQWSZW&sssrc=2349624&ssuid=ZqvfcQYkSbC&var=&widget_ver=artemis&media=COPY

Could you give a link for the fans?

Can confirm that this is the Firewire controller.
Had the same Motherboard for a while, firewire worked until at one point, i wanted to plug a USB controller into it and that thing burned down quite fast. Firewire didnt work afterwards anymore. 
So, as long as you dont need firewire, you are good to go

It’s not a connector as far as I can tell, I think it may be a controller for some kind of port around it

Ok so it’s probably just the controller for the FireWire port, plugged in a FireWire header and no luck with it. I guess it’s a good thing FireWire is dead

It’s not a connector as far as I can tell, I think it may be a controller for some kind of port around it

Yep.
Winning the silicon lottery with an old cpu is quite fun but also painful as you know you wont be the one benefiting from it....
I feel your pain.......

generally a good idea, this platform is really old, the Mobo probably don't have much life left, an OC might just be the thing that broke the camels back. 

If the games you play work fine with the 780, then go for it. But bear in mind many games will be modest, so it largely depends on what you like to play

Might actually be quite a good long term plan. As long as you get away with driver support (like @BlueScope819 already mentioned) and are fine with the slightly older hardware, you could definitely do it.

Hey there. I believe the only difference between the EVGA BQ and BR variants is the modularity (is that a word?) -- BQ is semi-modular, BR is non-modular.
Correction: There are some slight differences in cable length, power output, and build quality (e.g. Japanese capacitors, fluid dynamic bearing fans vs long sleeve bearing fans) between the two, but I'm not sure the differences it will be noticeable.
 
Source: EVGA 500 BQ and EVGA 500 BR by EVGA.

There is no variant of RX 570 with different cores, so you've got that clear.

If cheap is all youre looking for, something like this gigabyte board works just fine (https://www.amazon.com/dp/B079NYQQJJ?tag=pcpapi-20&linkCode=ogi&th=1&psc=1) but lacks some creature comforts like extra fan headers and wifi etc. Pair this with a cpu like the ryzen 5 1600 12nm. It is a refresh of the 14nm version of the 1600 and preformes similarly to the ryzen 5 2600, but it around $40 cheaper. (https://www.amazon.com/AMD-Processor-Wraith-Stealth-YD1600BBAFBOX/dp/B07XTQZJ28/ref=sr_1_1?keywords=ryzen+5+1600&qid=1582159007&sr=8-1) You've got a solid PC with that RX 580 and 16GB of ram.

Most likely $150 to $200 because it is a "used" system. I would advertise it at $200 and let negotiations take it wherever. Don't try to cheat out people though, as it's not cool.

Honestly I would pay like 100 max for that. I would list it at around 240 though and see if someone takes it. I've sold around 10 PCs on craigslist and have never found anyone willing to pay a premium for it being "custom built" 

I found a rx 560 for $100 at bestbuy

A few weeks ago I asked the community for ideas for a summer project. Someone reccomended making a tesla coil so I tried it and was shoked by high voltage wires and was admitted to the ER. But this still leaves me without ideas for a summer project. So if anyone has ideas for a project I could do that would be a great help.

Great idea, i'll try it

There is this, which is also fairly good. https://www.amazon.com/Cooler-Master-Hyper-T2-Heatpipes/dp/B00K7809O2/ref=sr_1_3?s=pc&ie=UTF8&qid=1502341244&sr=1-3&refinements=p_36%3A1253503011
 
But for $5 more this is much better https://www.amazon.com/DEEPCOOL-GAMMAXX-400-Heatpipes-Compatible/dp/B007JEMXYQ/ref=sr_1_7?s=pc&ie=UTF8&qid=1502341244&sr=1-7&refinements=p_36%3A1253503011

i havent caught up that much but it is maybe, I think not unless intel is really desparate. Intel would definately want to make a new socket and chipset to take our money

I'll save up a bit more for the more expensive one. Thanks!