I have a choice of getting this bundle for instance
https://www.scan.co.uk/products/gigabyte-x570-aorus-elite-atx-motherboard-plus-amd-ryzen-9-3900x-cpu-plus-corsair-vengeance-lpx-16gb
but I don’t have immediate pressure as my current PC while almost 5yo is still performing quite well.
so is it worth waiting for AMD Ryzen 4000 for desktop till September(?) ?
my current PC […] is still performing quite well.
You should wait until that statement is no longer true, or your needs change.
I would imagine the thing you should waiting for is the B550 motherboards. They should be cheaper with most of the features of the much more expensive X570. There will be people than need the extra features but if you are just gaming or general purpose computing the B550 would be more appropriate. What Ryzen CPU you drop in at this point is academic. They are interchangeable, figure out how many cores you want and see what you can afford. What you can’t afford today you might be able to afford tomorrow. Sell the old one on eBay to offset the cost of the new one. Get a 2700X right now it will run rings around your 5-year-old PC. Then once the market is right and you have the cash pick up something better. When the 4000 CPU are released the 3000 will drop in price. Then pick up a 3950X. 
I’m a cheapskate and that influences my thinking on this type of thing. I love performance but I can’t just drop huge chunks of cash on my PC. Sometimes you must be a bit clever about this type of thing. What do you really need vs what you want? always keeping an eye on what you can afford.
If you are still happy with the current pc performance,
then you could stick to it and wait.
But when not, then the X570 Aorus Elite + 3900x,
would be a good combo deal there.
Come back when that has changed.
Yeah, that … uhm, that one right there.
Maybe I should read a bit more first. 
Well this highly depends if the board manufacturers,
are going to come with decent b550 boards.
Because in terms of all the previous generation of B-series boards,
the vrm on those were pretty much all poor.
And not really great for a 3900x.
So yeah i´m looking forward to see what those new boards,
are up to in terms of vrm build quality.
I will definitelly make a topic on that.
If AMD releases X670 for Zen 3, I’d say X570 mobos will be the only ones with decent VRMs, powerful enough to handle the would be 4900X, and not the B550 mobos.
After reading y’all, I think, instead of getting that bundle I will get Ryzen 5 3600 CPU for now, and, fingers crossed, 4th gen would still be compatible with MB i am getting.
And, as at this time i am getting high-end GPU, possibly getting Ryzen 4th Gen CPU later will be the only upgrade part for years.
thank you all.
Ryzen 4000 will release in September, only 5 months away. You might as well go with the new 3100/3300X for now and save a few bucks that can be invested in a better Mobo or something…
Ryzen 4000 should close the performance gap with the 10900K, so yes it’s worth waiting. I have an X299 10900X at 5 GHz all-core with 4000 C16 56ns memory latency, higher memory bandwidth than a 3990X, and I’m still tempted to go TRX40 3960X. It would be a downgrade in every real world scenario, except number of cores on paper.
It wouldn’t be a downgrade if you actually do work that uses all the cores, though. Compile software, for example, and it will wipe the floor with a 10 core CPU regardless of your clocks or memory.
It’s primarily a gaming rig, but I need PCIe lanes for 4x NVMe RAID, full-bandwidth USB ports, Optane, etc. I would have waited for the 10900K otherwise.
Should I upgrade now and get the ryzen 5 3600 or wait for 4000 I have a amd phenom ii x4 955 lol yes I know it’s a dinosaur if I do upgrade to the 3600 what mobo would be good to get for the 3600 and would be good for the 4000 if I desire to get that later down the line thanks
If your system is still going just hold on for a couple more months. 3600 will still be here when 4000 comes out. So just hold on for now. Then you will buy whatever fits your budget better.
4x NVMe requires 16 lanes.
A gaming rig would presume 8 or 16 lanes for the GPU.
That is 24 or 32 lanes.
Ryzen is 20 general purpose lanes and 4 lanes going to the chipset.
If you really need 4 NVMe, you will split your partitions across cpu and chipset lanes, making the slowest partition dictate the speed of them all.
If you want 16 lanes for your GPU, you will only have 1 NVMe to the CPU and 3 partitions feeding through the 4 chipset lanes, dramatically limiting throughput.
Sounds like you might need Threadripper and its 56 general purpose lanes.