This is for one computer;
RAM:
http://www.amazon.com/gp/product/B00A14ZT8S/?tag=bom_tomshardware-20&ascsubtag= Fastest DDR3 RAM I could find, buy one set of 32GB.
SSD:
http://www.newegg.com/Product/Product.aspx?Item=9SIA2W02CZ2241 If all you plan on doing is running these web browser tabs on this computer this will help it open and run quickly. Not really needed, but will boost performance a bit.
Motherboard:
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128710
CPU:
http://www.newegg.com/Product/Product.aspx?Item=9SIA24G3RH8013&cm_re=I3-4170-_-19-117-543-_-Product
GPU:
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127763 Not sure if you need it, but here you go.
PSU:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139048 You probably don't need much more than this.
And just buy any case.
Someone a lot more experienced can probably help more, but I think this will work. I tried my best to make sure everything was compatible with each other.
Can you do some research to see how much RAM you would need to open all these tabs? I've never had to open that many tabs before, if you don't need 64GB of ram you can save a fair bit of money on the CPU, motherboard and the RAM itself.
Edit: I just opened a bunch tabs on google chrome (over 50 youtube, facebook and twitch tabs) and it only took 6.5GB of ram so you probably don't need 64GB of RAM, I will edit this in a moment.
Edit2: Alright, done, $350 cheaper and a better GPU for the price. I can re-post the other build if you REALLY want it.