What part(s) to upgrade for 4K video editing?

[Andy D]

My Dad asked me what he should upgrade as even just playing back 4K video he's recorded on his new Sony 4K camcorder seems slow and 'jittery'

His current system =
i5-3570K (not overclocked)
16 GB Ram
1 * 120GB SSD
2 * 2TB drives in Raid mode = 2TB
Geforce 670

Not sure he has the money to go for what I'd suggest which is maybe a new Ryzen 1700 system.
I've done some hard disk benchmarks and it looks like he's getting ~270Mbytes/sec from his Intel SSD, and ~310Mbytes/sec from his Raided mechanical drives.

I was going to suggest a 4790K plus a M.2 PCIe x4 adapter and fast m.2 stick.

Would this make much difference, or would the GPU be holding him back. Software is Adobe stuff as far as I know. Any suggestions please.

 

[EsaT]

Storage bandwidth won't limit playback.
For H264/MPEG4 AVC at least with GPU assist CPU shouldn't be problem.
Newer H265 again needs quite lot decoding power at high bitrates, but not sure if any device uses it yet.
Difference between video framerate and monitor's refresh rate could also ffect playback of PC.

Video editing and encoding needs lots of processing power.
Because of that some software can actually use lower resolution/quality proxy during cutting and editing phase so that user can then go to do something else while leaving PC crunching full resolution final render.
Also GPGPU processing can be used for compression, though CPU based encoders have best quality.

 

[ExoMale]

Overclock the processor or get an 8 core 16 thread ryzen, get more than 16gb ram and either a 580 or 1080 unless the 1070 be good enough.

I don't know how demanding that recording be, but it's better to have more than enough power than just the right amount as reserve is always good option.

 

[Andy D]

Ok so as a partial step rather than whole mobo, CPU, and RAM, go for GPU upgrade first.
Thanks