7820x versus 3900X

[StealthArsenal]

Hello everyone,

 

Been a couple of years now, since I fully rebuilt my system.  With that said, I have kept tabs on all the latest and greatest, but just hadn't  really wanted to upgrade to anything yet.  At least not without seeing AMD's new offering.  So with that said, I am considering the switch from my 7820X over to the 3900X.  Obviously some of the benchmarks (there aren't a ton with the 7820X in there) I have seen in the many many youtube video yesterday show the 7820X pretty significantly below anything current.  This of course I expected.  What I am looking to do, is get a bit better gaming performance but also better multi-threaded performance when I am drafting in AutoCAD and/or Revit.  Obviously for me, I can sacrifice some single threaded performance a bit from say the 9900K (but am I really).   Am I losing much of anything from dropping from quad channel back to dual channel.  Obviously, I am gaining 4 cores, significantly more threads, cache and pcie lanes.  Logic and everything I have read would tell me that the 3900x is better in everyway to the 7820X and the x299 platform.  From a cost perspective, it doesn't seem too logical to grab a higher end X299 cpu. 

 

With that out of the way, I was thinking along the lines the 3900X paired with an Aorus Master or Asus Crosshair with 32gbs of 3600mhz Trident Z memory.  The rest of the system in my signature would remain intact.  This would simply be a cpu, board and ram swap out. 

 

I guess what I am specifically asking, is there enough of a performance increase to justify.

 

Thanks

Chris

[.Apex.]

10 minutes ago, StealthArsenal said:

From a cost perspective, it doesn't seem too logical to grab a higher end X299 cpu. 

but buying a CPU+Motherboard+RAM is the same price as another x299 CPU, it doesn't make any sense, it would be smarter to buy a used 7920X or something, or later down the line when they get cheaper
 

13 minutes ago, StealthArsenal said:

I guess what I am specifically asking, is there enough of a performance increase to justify.

You won't notice anything in gaming since you're at 1440p, and Autocad is single-threaded so having more cores doesn't help you at all, same with Revit, though Revit does benefit from more cores when rendering but is that really justifiable to pay an extra 1000$+ for a little improvement in render time?

 

20 minutes ago, StealthArsenal said:

I am gaining 4 cores, significantly more threads, cache and pcie lanes.

7820X has more PCIE lanes

[.Apex.]

According to benchmarks the 7820X performs very closely to the 9900K in games, and better in productivity because of Quad Channel and cache, so if you wanna see how it compares against the 3900X just look at the 9900K

[For Science!]

55 minutes ago, StealthArsenal said:

-

Well I guess since its been 2 full years since the release of the 7820X so you do qualify for the term "a couple of years" ;-). There is of course no real way to know whether it is an improvement enough unless you elaborate further (and honestly even if you did, its still hard to recommend). For instance, for my workload there are overnight jobs that take say for example 14 hrs to complete. So even if a processor is 30 percent faster, it is still an overnight job (i.e. instead of finishing at 8 AM, it finishes at 4 AM), thus not changing my workflow despite it increasing the speed (I don't achieve more jobs per day).

 

On the other hand some jobs can be scheduled and so the CPU is pinned at 100% load almost a week straight, then it makes a difference to get 30 % more speed since that will affect how many jobs per week I can run.

 

At the end of the day, if you aren't making money out of the system, then any cost associated with it "is not worth it" since you can't recuperate the costs.

[GoldenLag]

54 minutes ago, StealthArsenal said:

From a cost perspective, it doesn't seem too logical to grab a higher end X299 cpu. 

There hasnt really been a reason for going x299 since the 8700k was a thing....

[StealthArsenal]

@_Syn_

 

Thanks for responding. 

 

I'm not sure I agree with the single core usage of autocad/revit regardless of what they claim.  I am maxing out 8 cores on my 7820X and all six cores on my 8950HK in my work laptop.  That's a debate for another time. 

 

As far as gaming benchmarks and such, I am significantly behind the 9900K even overclocked on my 7820X.  I did see some of what you were referring to, which has me a bit confused I suppose.  I was thinking something completely different with lanes, so I apologize about that.  For some reason I was thinking 40's on the 3900X.  I knew the 7820X was 28, so I should've looked that up before I said anything. 

 

I completely agree with the quad channel comment.  In my head I was thinking this, but I wanted a confirmation. 

 

If I bought the 3900X, I have another system.  That was kind of the idea, but I did not mention this.  I would move my 7820X into projector gaming status or upgrade a family member who renders out production on a 3700K. 

 

I guess the other way to look at it is X299 is going to be a dead socket soon?  I dunno.  I don't have to make this move, I was just contemplating it.  It just seems the AMD systems now are just better and I really want AMD to be good again. 

 

[.Apex.]

2 minutes ago, StealthArsenal said:

I guess the other way to look at it is X299 is going to be a dead socket soon?  I dunno.  I don't have to make this move, I was just contemplating it.  It just seems the AMD systems now are just better and I really want AMD to be good again.  

X299 is old and useless compared to what Ryzen offers today, but I mean you already have it so it's hard to justify this kind of upgrade if you're expecting a significant jump in performance, which I personally don't think would be significant, but if you wanna have a separate system either way then go for it I guess, it's definitely a difficult question, it's up to you

 

8 minutes ago, StealthArsenal said:

I'm not sure I agree with the single core usage of autocad/revit regardless of what they claim.  I am maxing out 8 cores on my 7820X

Is that during rendering or sketching/drafting? rendering will always use all cores

[StealthArsenal]

@_Syn_

 

If I load up Civil3D and say externally reference in topography, other drawings.  Then let's say I draw an alignment and start using pressure networks and create a profile, I will start utilizing all the core.  Same goes for vertical and horizontal curves and profiles.  Both Revit and CAD are resources monster.  I started at work with a 4 core, 8 thread machine then went to the 8950HK and both programs functions 100 times better.  Now I bring my files over to myn desktop and draft because that's smoother and faster yet.  

 

I get the consensus behind having the platform already.  I'm not 100% saying I'm switching, I'm just thinking maybe from an upgrade stand point, maybe Gen 3 is worth it.  I don't really know.  Would love to see some additional benchmarks, but what I did see on OC3D a bit ago is the x299 getting smoked (aside from two XE models).  

 

I don't mind purchasing the AMD system, but then again, maybe a 2080TI might be nice or another Alienware 34".  I don't know.  I'll see what I can find in additional benchmarks and make an informed decision. Thinking of possibly selling off my x299 if I do switch.  I know what I was thinking, but I had to be realistic and say to myself, there is no way you will use the second system. 

 

Thanks

[.Apex.]

58 minutes ago, StealthArsenal said:

I get the consensus behind having the platform already.  I'm not 100% saying I'm switching, I'm just thinking maybe from an upgrade stand point, maybe Gen 3 is worth it.  I don't really know.  Would love to see some additional benchmarks, but what I did see on OC3D a bit ago is the x299 getting smoked (aside from two XE models).  

 

I don't mind purchasing the AMD system, but then again, maybe a 2080TI might be nice or another Alienware 34".  I don't know.  I'll see what I can find in additional benchmarks and make an informed decision. Thinking of possibly selling off my x299 if I do switch.  I know what I was thinking, but I had to be realistic and say to myself, there is no way you will use the second system. 

3900X will definitely perform better, but the question is how much better, wait a few days so that people benchmark more of these CPU's, it's too early right now

[StealthArsenal]

@_Syn_

 

You are absolutely right.  I wasn't jumping in it right this second.  I have a microcenter local, so I can go pick everything up whenever. 

 

I guess I seeing x299 as pretty much dead now aside from two outliers.

 

Thanks

[StealthArsenal]

@_Syn_ 

 

Just wanted to clarify one other thing.  I was at work when I originally posted this thread.  Where I was going with the PCI Express lanes actually was the 24 on the cpu, but the chipset has another 16 usable (20 total) for a 36 usable/44 total. 

[DogKnight]

This is something I have been considering also. I have a 7820x system very similar to yours in spec. 

I would love to go for a 9940x as an upgrade, but the cost is more than a 3900x and motherboard combined. 

There would be some gains in performance I suspect. One downside being that the market for selling x299 is going to be awful. And that is if Intel doesn't go ahead and slash prices on 2066 CPU's given the change in competitive landscape. 

Earlier HEDT platforms retained their value more as people can buy old server xeon CPU's that were overclockable. This allowed them to get a lot more cores than the standard desktop offerings for that generation and build a reasonably cheap PC. However they stopped supporting Xeon overclocking with X99/2011-3 from memory. 

 

I am glad to see the new Ryzen chips offering such great price/performance. I have no doubt my next PC will be Ryzen based. But I don't think it would be worth the $1k + that the change would cost. 

Note that I am in Australia if the dollar figures I am referencing seem odd. 

[.Apex.]

13 hours ago, StealthArsenal said:

@_Syn_ 

 

Just wanted to clarify one other thing.  I was at work when I originally posted this thread.  Where I was going with the PCI Express lanes actually was the 24 on the cpu, but the chipset has another 16 usable (20 total) for a 36 usable/44 total. 

X299 has 24 PCIE lanes, so that would be 52 total, but it doesn't matter either way if you only have a single GPU, it starts to make a difference if you wanna use 3-way+, or maybe 2-way and PCIE SSD's running on CPU lanes, but I would suggest you connect the SSD's to the Chipset lanes instead (X570)

[pas008]

25 minutes ago, _Syn_ said:

X299 has 24 PCIE lanes, so that would be 52 total, but it doesn't matter either way if you only have a single GPU, it starts to make a difference if you wanna use 3-way+, or maybe 2-way and PCIE SSD's running on CPU lanes, but I suggest you connect the SSD's to the Chipset lanes instead

depends though how much data is pulled at once cuz isnt the still  constricted to 4x speed from the chipset

[.Apex.]

23 minutes ago, pas008 said:

depends though how much data is pulled at once cuz isnt the still  constricted to 4x speed from the chipset

Yes but it's Gen 4.0, so it should be enough to handle 2 SSD's at once, I know there's other things connected to the chipset and that might bring it down, but still I think it should be fine getting at least 1GB/s + on both SSD's at the same time, full x4 4.0 bandwidth is 7.5GB/s

[pas008]

46 minutes ago, _Syn_ said:

Yes but it's Gen 4.0, so it should be enough to handle 2 SSD's at once, I know there's other things connected to the chipset and that might bring it down, but still I think it should be fine getting at least 1GB/s + on both SSD's at the same time, full x4 4.0 bandwidth is 7.5GB/s

gen 4?

he should have his nvme to cpu lanes(if mobo allows it)

hdds and sata ssds i agree

[.Apex.]

55 minutes ago, pas008 said:

gen 4?

he should have his nvme to cpu lanes(if mobo allows it)

hdds and sata ssds i agree

Yes but most Ryzen consumer boards only have 1 M.2 slot connected to the CPU lanes while the others are through the Chipset, and he has 2 SSD's, and I thought X299 has 2 M.2 slots connected to CPU lanes but nevermind they're actually all through the Chipset, so it only matters if he's going 3-way SLI because X570 doesn't support 3-way

[StealthArsenal]

Whoa, didn't have the opportunity to check this during the day today.  Definitely no 3-way SLI, but I can go 2 way SLI as I do have another 1080TI it just isn't in the system right now.  Now one thing I do have, but have not put in yet, is a third NVME drive.  I may retire my Pro drive, but that is something I have not decided upon as of yet. 

 

I am half tempted to grab a processor and mobo from Microcenter and put it head to head with my current system and see what I find out. 

[StealthArsenal]

Alrighty, so I have been doing some testing today.   Definitely getting some very interesting results. It's like a catch 22 right now.  For clarity, here are my testing rigs:

 

- 7820x                                                     vs.   3900X

- Aorus X299 Ultra Gaming                      vs.  Crosshar VIII X570 Hero

- 32 gb - 3000 Mhz ram (Vengenance)    vs.  32gb - 3200 Mhz Ram (Vengenance)

- 1080TI FTW 3                                       vs. 1080TI FTW 3

- Clean install Win 10 Pro                       vs. Clean install Win 10 Pro

 

I was primarily testing out of the box with stock settings, but I also went ahead and clocked my 7820x up to 4.4 ghz on all cores to better match up with the 3900x which was turbo boosting and staying consistently at 4.3 to 4.4.  The 3900X also maxed out at 4.4-4.6 on all cores.  All these numbers came from CPUZ and HWMonitor.  I did not overclock the 3900x or overclock the mesh on the 7820X. 

 

If I look at Cinebench. R15 and R20 are quite a bit faster multicore and a bit faster single core. With R20, we are looking at 7105 multicore and 503 single core on the 3900x vs. 4219 multicore and 435 single core on the 7820x. R15 on the other hand saw 3077 cpu and 198 single core on the 3900x while the 7820x was 1774 cpu and 190 single core.

 

Looking at time spy extreme, I got a CPU score of 4495 on the 7820x. With the 3900x, cpu pulled 6596 with 3200mhz ram. Graphics scores were identical obviously due to the same graphics card.   

Fire strike ultra had the 3900x physics at 27932 with combined of 6936 while 7820x physics was 21145 with combined of 7071.  I also ran Fire strike extreme and the 3900x was at 28015 physics and 6928 combined.  The 7820x on the other hand was at 19174 physics and 5191 combined.  
 

I tested just two games because I honestly wasn't expecting too much of a difference.  

 

Tomb Raider (7820X) - Min FPS = 110, Max FPS = 120, Avg FPS = 119.1

Tomb Raider (3900X) - Min FPS = 106, Max FPS = 120, Avg FPS = 118

 

Metro Last Light (7820x) - Avg FPS = 97, Max = 175.65, Min FPS = 23.49

Metro Last Light (3900X) - Avg FPS = 100, Max = 185, Min FPS = 28.43

 

There is still room I suspect to overclock the 7820X more.  I could mess with the mesh overclocking and bring the multiplier on the cores up more.  I am on water, so I have a bit more headroom from a thermal perspective to work with.  I also had the 7820X at 1.25V at the 4.4.  Flipping to the 3900X for a moment, as I mention it was clocking up on boost to 4.3-4.4 but was doing so at 1.475V.  I suspect I can maybe overclock a bit on the 3900X, but it would appear the 7820X might clock further.  I clocked it on the fly without a crash so I think we can go further here.  

 

I don't know, I could make the argument to keep the 7820X and return the 3900x or keep it.  I could also see about faster ram in the X299 system and hang onto it until the 3950X or find say a 9900X and drop into my X299 board.  

 

At this point, I would say it probably is an expensive platform swap for not too much difference.  I would probably be better with a 9900K.  I do have a 2080TI coming tomorrow, so either system will do fine with it.  Not sure, maybe I am looking at this all wrong.

[bignaz]

I say go for it. Sell your old stuff why it still has resale.

 

Your ram is fine. The 3900x is not as ram dapendent as the previous versions and it will be an extremely small gain and not worth upgrading.

 

As for Mobo. There all about the same. They all clock the same. Pick what looks best or whatever features you like.

[StealthArsenal]

@bignaz

 

I'm going to keep the X299 for now.  Going to wait and see what comes down the pipeline.