Ryzen 7 3700X vs Ryzen 9 3900X

Hardware Build a PC
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I’m new to these forums, so appologies in advance if this is posted at the wrong place.

I’ve ordered a Gigabyte X570 I Aorus Pro and RX 5700 XT, but undecided on CPU.

All the reviews so far seem to either have the 3700X and the 3900X on par or even the 3700X beating the 3900X. Wendell’s review of the 3900X however seem to favor the 3900X over the 9900K from Intel.

The 3700X is available to order right now, while the 3900X is expected in stock later this month.

Any help to decide between these two is appreciated.

Atm I’m a bit torn due to the 3900X having 12 cores and might be a better long-time investment, but the 3700X seem to have the same performance right here and now.

Edit:
Games I’m currently playing:
Battlefield 5
Apex Legends
The Division 2
No Man’s Sky

Edit 2:
I’m playing on a 1440p 144hz monitor.

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Hey, welcome…

run while you still can

Here’s the thing:
Do you do anything else with your pc? Streaming, vudeoediting, 3d modeling, anything else? If yes - then get the 12 core. It runs circles around everything else. The 1 FPS gaming difference is worth the huge thread count.
If you don’t do anything power hungry in your pc and just game on it, get 3600X… Much cheaper and games the same as the higher end ryzens…

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As of right now, I can barely even game :stuck_out_tongue:
Intel i3 with 4 cores locked at 3.6ghz struggles in The Division 2 and No Man’s Sky, so I haven’t played those much.

I had originally ordered the Ryzen 5 3600, but decided to cancel as I wanted something a bit more future proof. Seeing as this might be the last gen of CPU’s to slot right into the AM4 socket.

I consider myself a bit of a geek, so the 3900X is screaming “buy me, buy me”… But if it has no advantage in gaming, I’d be far better off getting the 3700X and get a good set of memory or a PCI4 SSD.

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Pure gaming - no advantage…
To be fair 3600 is kinda beating my 1700X 8 core in everything, so it’s kinda super great for the price… And a proof you can’t really future proof anything.
You know 2 generations down the line the 8 core will spank the 3900X at absolutely everything…
But yes, I can bet even the 16 core will not be any faster in gaming than the 3600 for example…

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True. Future proofing doesn’t really exist in this game.

Is the 3600X faster than the 3700X or are they on par? I see the base clocks vary, while the boost clock is the same.

3600X is not in stock anywhere

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Screenshot_20190710-022850
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It’s the same core in all CPUs so the only difference in gaming would be the clock speed…
All CPUs are around 4.4-4.6 so it’s pretty much the same.

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Last question, I promise. I’ve kinda made up my mind already.

If I were to dabble into the realm of streaming, would the 3700X be on to the task?

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Extra cores would help massively with streaming. 3700X would have more room to breathe than the 3600X.

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Guess I should have specified which CPU’s I was comparing in my head, hehe.

3700X vs 3900X

Linus shows the 3700X and 3900X to be quite similar in that regards.

Linus
Linus.JPG1106×633 62.2 KB

Guess I should just order the 3700X already… eh?

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The Canadian bastard? He is an ass… I don’t watch his garage for a long time now…

In gaming and streaming 3700X can do everything 3900X can do. 3900X can do a bunch of other stuff that 3700X would struggle with. If you don’t do any of those things 3900X is pretty much just a waste of money.

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Perfect. Exactly what I needed to hear… errr. read.

Placed an order for the 3700X :smiley:

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3700x is a good choice. Unless you needed the extra 4c/8t of the 3900x or had an application that could take advantage of the extra L3 cache, the 3700x is a better cost effective processor (could get a 3700x and an x470 motherboard for the price tag of a 3900x)

Ordered an 3700x myself because I couldn’t justify the extra cost for the 3900x, even though I wanted it :stuck_out_tongue:

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So my 3700x was a bit shy about it’s boost clock but the 3900x was better in that regard. The reason my 3900x is higher than almost everyone (but some folks had a 3900x at parity with the 9900k too) is because I got the stable pbo working and had tight timings. It wasn’t dramatically faster. Just a hair.

The sketch uefis if you enable pbo you actually get a non trivial perf regression.

I see pbo a bit like mce. If no perf is left on the table the 3900x will often but not always pull ahead of the 9900k . But like the 9900k you go far outside that 100ish watt corridor.

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Is this all down to luck? Did you get a good sample 3900X and a bad 3700X?

The new boost clock speed is really confusing. To make it easy for everyone they should have kept the old way with a guaranteee max boost.

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I suspect cooling for higher clocks is better on the 3900x due to the multiple CCDs.

Instead of 1 fully loaded CCD with 8 cores of heat in that area, the 3900x will have 2x 75% active CCDs. I.e., 75% of the heat to dissipate in each core complex die.

Following not in reference to wendell… but the OP
Also indicated in another thread on here, the 3900x has 2x the memory write bandwidth of the 3700x due to the two dies.

Of course, it is more expensive, but my advice (based on reading a bunch about them both this week) would be:

  • If you are or are planning to do VFIO - go 3900x. Both for additional cores and memory write bandwidth.
  • If you’re flush with cash, the 3900x will be faster for heavy multitasking.

The impact to total system BOM cost is not huge. Yeah its a more expensive CPU but your build cost won’t go up a huge percentage… you’ll get up to 50% more throughput for much less than 50% more money in terms of total system cost (motherboard/RAM/storage costs are constant).

If you already have an AM4 box and aren’t buying everything new, then the above cost vs. performance advice may differ…

The times the 3900x is getting beaten in gaming is likely (IMHO) due to cross-die communication like with previous gen Ryzen. If this is important to you, go 3700x.

But IMHO i think the tradeoff in those very rare cases is worth it for the potential VFIO memory bandwidth and more cores.

But either CPU will be a great choice, IMHO.

edit:
Also yes, as above future proofing is not a thing (though with AM4 at least your motherboard will likely get future CPU support).

Buy what you need today, etc. - but if you think your workload can benefit from more cores, i’d go 3900x. And if your workload can’t benefit from more cores… i’d suggest maybe 3600x (instead of the 3700x), and put the money away you’d spend on 3700/3900 for next year’s 4000 series.

I think i just kinda ruled out the 3700x to be honest. For simple gaming, etc. the 3600x is plenty. If you need more cores, then buy a 3900x - if you can afford it (and if you can’t, save a few more weeks or whatever). On core hungry workloads the performance improvement will be more than worth the additional spend - assuming you’re doing an entire system build.

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shouldn’t the 40 additional watts make it impossible for the 3900x to make cooling better?

To be honest i think the 3700x is a great multipurpose CPU, i’ll probably put it into my Media/Gaming/Work PC that sits in a tiny case behind my TV.

Another thing that would be interesting to me is if somebody did some testing on what kind of workloads are limited by memory write bandwidth. I did some testing with my i5 4690 and as soon as i do something that isn’t just a simple multiplication i am always limited by the actual computation and not the memory. I wonder if this is still the case with 4 times the cores/threads. But i’ll probably upgrade to a 3700x soon and i can just run the program again to check it.

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Hey @wendell by chance have you tried to see if VMware ESXi boots with the Ryzen 3000 CPUs? They’d make really great and cheap homelab CPUs and I’m wondering if ESXi will PSOD or not with them

Ideally testing both 6.5U3 and 6.7U2

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Any major differences between memory speed and latency?

I can’t seem to find any 16GB dimms at 3600Mhz c16.

Which of the following is the best pick:
3200Mhz 14-14-14-34
3466Mhz 16-18-18-38
3600Mhz 17-19-19-39