Recommended Hardware for Character Animator?

Hi all, 

I think I overdid it, I try to build a scene in 4k and 60 frames per second.

I understand, that the actual scene window will eventually not work in real time (orange indicator tells me either ~20fps (AMD Radeon R9 290x Graphics Card) or ~55 fps (Intel 6500 graphics chip, as those are the 2 computer I can test it on).

While not great, one can still live with  these refresh rates

But when exporting a 60 second scene via Media Encoder, it really makes no difference, which settings are choosen (h264, MPEG2, Quicktime, SD, HD, UHD, 320x200, I tried it all), it ALWAYS takes more than 60 minutes to encode 60 seconds of scene time (by the way, sometimes the whole Timeline is exported, sometimes only the work space, have not figured out how to influence this). 

I even tried Dynamic Link into Premiere, does not help, the scrubbing performance now equals render time in Media Encoder.

Same with After Effects via Dynamic link.

I now suspect, that h264 is the exchange format used between the programs. And both my machines are not really up to the tasks with their graphics hardware (R9 is rather outdated, Intel 6500 is just nice for Office and never was meant for this)

So, does anybody can suggest a working hardware setup that allows for reasonable encoding results?

Thanks a lot

M.