Question Should I buy the 3800x instead of the 3700x?

[Dave3000]

I might be going to Micro Center tomorrow and buy some parts for an upgrade. I was considering the 3800x instead of the 3700x since the price difference between the two is only $30 at Micro Center. I plan to keep my next CPU for at least 3 years, so the extra $30 means nothing to me over a 3 year period. I was going to get a 9900KS but the markup from retail pricing is too much for that one, so I won't buy the 9900KS out of principle, even though I can afford it. Since I'm mainly gaming, I don't really need 12 cores/24 threads, so I'm not considering the 3900x anymore. I'll be happy with fast 8 cores/16 threads for at least 3 years I believe. So is it worth it for me to get the 3800x instead of the 3700x?

 

[UsandThem]

So is it worth it for me to get the 3800x instead of the 3700x?

Nope.

Plenty of reviews show it's just not worth it.

 

[Markfw]

The 3900x with 6+6 cores is actually faster than the 3800x with 1x8 cores (ccx wise). If you can afford the 9900ks, get the 3900x instead, its faster than the 3800x.

Its at the 499.99 msrp right now.

 

[Dave3000]

Isn't the 3900x 4 CCX's with 3 cores in each one, basically, 3+3+3+3 cores. The 3700x and 3800x have 2 CCx's with 4 cores each in 1 chiplet (a chiplet is not a ccx) which make them 4+4 cores.

 

[VirtualLarry]

Isn't the 3900x 4 CCX's with 3 cores in each one, basically, 3+3+3+3 cores.

I'm curious about this too, but I don't currently believe that to be the case.

In Zen and Zen+ archtecture (basically same arch. arrangement, just a small shrink that enabled higher clocks / greater power efficiency between then), they had CCXs, which (simplistically) was a grouping of four CPU cores, and a slice of L3 cache. Each Zen/Zen+ die had two of those CCXs.

Newer Zen2 architecture, has them arranged in a CCD, which houses two CCXs, and talks to an "I/O die" to connect to memory. There can be multiple dies with CCDs connected to the I/O die. Anyways, however it works, it supposedly did away with the "NUMA penalty", which means that for all practical purposes, AMD no longer has to "balance" CCXs to equal core counts.

So, I believe, it's possible to bin a CPU die with one CCD, containing two CCXs, with one CCX containing only two good cores, and the other CCX containing all four good cores, as a six-core CPU die, and pair up one or two of those dies with an I/O die, for a Zen2-architecture Ryzen 3000-series CPU.

Certainly, if this is true, and I haven't seen much about it, or anything against this idea, then it would make defect-related binning a lot easier.

I could be completely off-base here, though, and possibly, if they have a CCD, with one CCX with four good cores, and one CCX with one bad core, then they HAVE TO disable one CCX in the four-core CCX, to make 3+3 cores in each CCX, to sell as a 6-core CPU die. I think that would be an unfortunate outcome, though.

*** Anandtech main page editors, maybe a deep dive on this issue would make a good article, what with ThreadRipper 3 coming up now too. (Maybe it's covered in that article? Will have to read it.)

 

[ondma]

If your primary use case in gaming, maybe consider the regular 9900k or the 9700K. With decent cooling, either of those should overclock within a couple hundred mhz of the 9900KS.

 

[Dave3000]

Will games that use up to 4 cores perform just as well on a 3900x as they do on a 3800x? The reason I ask is because I wonder if there is less inter-core latency on a CCX that has 4 cores vs a CCX that has 3 cores then has to access the 4th core on the 2nd CCX. I'm sure there are still plenty of games that only use 4 cores or less.

 

[tamz_msc]

Will games that use up to 4 cores perform just as well on a 3900x as they do on a 3800x? The reason I ask is because I wonder if there is less inter-core latency on a CCX that has 4 cores vs a CCX that has 3 cores then has to access the 4th core on the 2nd CCX. I'm sure there are still plenty of games that only use 4 cores or less.

It doesn't matter because of the way thread scheduling works in Windows.

 

[Topweasel]

Will games that use up to 4 cores perform just as well on a 3900x as they do on a 3800x? The reason I ask is because I wonder if there is less inter-core latency on a CCX that has 4 cores vs a CCX that has 3 cores then has to access the 4th core on the 2nd CCX. I'm sure there are still plenty of games that only use 4 cores or less.

The CPU's and Window's don't really work that way. Yes in a perfect world if you kept all and absolutely all comm within a single CCX its the only situation where you would see a latency benefit. But honestly check out the Zen 3 review here, they used a 3700x (I don't think AMD was shipping 3800x's to reviewers). With the efficiency of 7nm, the 3700x and 3800x generally perform about the same in games. It's in multitasking (re all core usage) that the extra power allotment of the 3800x allows it to pull away. The 3700x and 3900x were neck to neck with maybe 1-2 outliers where one was more than 1% better in any given scenario.

Basically the IO die is really smart and pretty great in the end and it allows a dual die setup like the 3900x and will with the 3950x run just as well as a single die chip, in games. It's why everyone under the sun seems to prefer the 3900x over even the KS outside very strict gaming only scenario's. The 3900x is very much a have your cake and eat it too processor when it comes to gaming and Multitasking/prosumer workloads.

 

[StefanR5R]

So, I believe, it's possible to bin a CPU die with one CCD, containing two CCXs, with one CCX containing only two good cores, and the other CCX containing all four good cores, as a six-core CPU die, and pair up one or two of those dies with an I/O die, for a Zen2-architecture Ryzen 3000-series CPU.

This would create an imbalance between CCXs WRT 1) level-3 cache available per core, 2) connectivity to the I/O die available per core. Especially the cache issue could create nightmares at the firmware and kernel level, I suspect.

 

[DrMrLordX]

@Dave3000

3800x is a better bin. If you are serious about cooling the chip and want to hit the highest clocks possible with Matisse, a 3800x may be your thing. Just be advised that it probably won't ever boost as high as a 3900x (due to microcode), but in terms of all-core OC, the 3800x will probably top a 3900x.

Also bear in mind that a 3900x has more L3 cache, and it has full memory write bandwidth (unlike a 3600, 3700x, or 3800x that have 1/2 memory write bandwidth, which is kinda weird). Overall I think the 3900x is the fastest gaming CPU AMD has right now even if you don't need the extra cores/threads. But a 3800x can pull ahead if you need an all-core OC and are serious about putting in the work necessary to test & tune it. A 3800x running all-core OC of 4.5 GHz in games would be pretty impressive.

 

[Kenmitch]

Only thing I can add is make sure you get an adequate cooling solution. The stock fans included with both of your potential candidates aren't the best, but will get you buy til you decide on a worthy solution.

 

[EliteRetard]

I might be going to Micro Center tomorrow and buy some parts for an upgrade. I was considering the 3800x instead of the 3700x since the price difference between the two is only $30 at Micro Center. I plan to keep my next CPU for at least 3 years, so the extra $30 means nothing to me over a 3 year period. I was going to get a 9900KS but the markup from retail pricing is too much for that one, so I won't buy the 9900KS out of principle, even though I can afford it. Since I'm mainly gaming, I don't really need 12 cores/24 threads, so I'm not considering the 3900x anymore. I'll be happy with fast 8 cores/16 threads for at least 3 years I believe. So is it worth it for me to get the 3800x instead of the 3700x?

Siliconlottery ( https://siliconlottery.com/ ) bins and sells overclocked CPUs, acording to them the 3800x is the highest clocking chip.
How much that matters is up to you, the difference is only 100-200 MHz.

https://imgur.com/MBHUxGI

 

[ondma]

Siliconlottery ( https://siliconlottery.com/ ) bins and sells overclocked CPUs, acording to them the 3800x is the highest clocking chip.
How much that matters is up to you, the difference is only 100-200 MHz.

https://imgur.com/MBHUxGI

Where did you get that chart? I followed your link, and also went to the site directly, and they dont even have any AMD cpus listed. Well, except for the 3950x, which is not available yet and has no clocks listed.

 

[EliteRetard]

Where did you get that chart? I followed your link, and also went to the site directly, and they dont even have any AMD cpus listed. Well, except for the 3950x, which is not available yet and has no clocks listed.

https://siliconlottery.com/pages/statistics

Happens to be the bottom of the page.

They do appear to be sold out of just about everything right now.

 

[UsandThem]

https://siliconlottery.com/pages/statistics

Happens to be the bottom of the page.

They do appear to be sold out of just about everything right now.

They were pretty much selling the 3700X and 3800X below retail price after they binned the CPUs. I'd be very surprised if they sold any more of that series (outside of the 3950X when it first launches).

They found there just isn't much overclocking potential for the Ryzen 3000 series.
https://www.tomshardware.com/news/silicon-lottery-binned-ryzen-3000,40010.html

The takeaway here is confirmation the AMD processors do not have a lot of overclocking headroom, just as their predecessors. Silicon Lottery (SL) binned Ryzen based CPUs in the past and ran into the same situation. After a few months, they stopped selling those processors as demand simply dried up.

SL posted on reddit the other day to clarify some questions about the launch and share some observations. The company shared its stance about why it bins the CPUs with such little headroom stating, “…as long as we can break even on the labor, I don’t mind carrying them a short while and gathering some overclocking statistics to add onto our chart,” which is something we love to hear.

 

[JustMe21]

Does anyone have any comparison of all the maximum clock speed of all the cores on a 3800x compared to the 3700x? While it seems like the scheduler is trying to keep most of the processes on the 2 faster cores, I would hope the 3800x would have more cores that could achieve higher clock speeds so processes can be distributed better across more than just 2 cores thus extending the overall life of the processor. I hope the Zen 4000 series goes back to having all cores have the same max clock speeds, not just some of the cores.

 

[Markfw]

Does anyone have any comparison of all the maximum clock speed of all the cores on a 3800x compared to the 3700x? While it seems like the scheduler is trying to keep most of the processes on the 2 faster cores, I would hope the 3800x would have more cores that could achieve higher clock speeds so processes can be distributed better across more than just 2 cores thus extending the overall life of the processor. I hope the Zen 4000 series goes back to having all cores have the same max clock speeds, not just some of the cores.

Unless you overclock with high voltage, that processor will run until WAY after its usefullness. I have processors that are 15 years old and still running.. The only one I ever burned out was an Athlon XP 1700 that OC'ed the crap out of.

 

[DrMrLordX]

@JustMe21

If you use static OC, you can probably hit 4.4 GHz-4.5 GHz with a 3800x. Depending on cooling and workload.

 

[EliteRetard]

@JustMe21

If you use static OC, you can probably hit 4.4 GHz-4.5 GHz with a 3800x. Depending on cooling and workload.

Doubtful, take a look at the chart I posted from siliconlottery. Only the top 20% of 3800x hit 4.3GHz all core.
4.4 - 4.5GHz flat OC is highly unlikely on current Ryzen.

 

[DrMrLordX]

Doubtful, take a look at the chart I posted from siliconlottery. Only the top 20% of 3800x hit 4.3GHz all core.
4.4 - 4.5GHz flat OC is highly unlikely on current Ryzen.

That's in AVX2-heavy workloads like Prime95 SmallFFTs (or worse, custom FFTs). For stuff like CBR20 or Blender, I've gotten my 3900x stable @ 4.4 GHz before at an acceptable voltage. Then I went for max RAM OC and lost a few clocks. In any case, a 3800x is binned better and should clock higher than a 3900x.

 

[EliteRetard]

That's in AVX2-heavy workloads like Prime95 SmallFFTs (or worse, custom FFTs). For stuff like CBR20 or Blender, I've gotten my 3900x stable @ 4.4 GHz before at an acceptable voltage. Then I went for max RAM OC and lost a few clocks. In any case, a 3800x is binned better and should clock higher than a 3900x.

I suppose if your goal is "stable enough" in a particular application and that works for you, nothing wrong with that...
I personally want my computers as stable as possible even under stress testing, and that's probably the only way to bin and resell CPUs.

 

[DrMrLordX]

I suppose if your goal is "stable enough" in a particular application and that works for you, nothing wrong with that...
I personally want my computers as stable as possible even under stress testing, and that's probably the only way to bin and resell CPUs.

That's the complicated part about Matisse. Theoretically, I could stabilize my CPU @ 4.4 GHz in Prime95 SmallFFTs, but the heat is too great under that scenario. It's just not reasonable to run that workload at that clockspeed without subambient cooling: LN2, phase, or what have you. Note that the problem is due primarily to hotspots. You kind of have to create a static clockspeed/voltage profile on an application-by-application basis, and then group the applications.

In my findings, stuff like Prime95 and y-cruncher produced the worst hotspot temps, so I always run those in default (no OC) mode and let the boost algorithm handle them, with some tweaks to LLC and voltage offsets to keep temps in check. Linpack and certain PrimeGrid workloads also fall under this heading.

Blender was less-stressful, but it was still impossible to stabilize on my chip at speeds above 4350 MHz. So it sort of had a category all to itself.

Everything else was stable up to 4.4 GHz. It's easy to switch settings with Ryzen Master when necessary. No rebooting required.

 

[yeshua]

In terms of performance these two CPUs are very very similar however the 3800X consumes more power (around 30W):


itvision.altervista.org

Which means either you have to buy a beefier cooler or enjoy worse acoustics/temperatures under load.

 

[BTRY B 529th FA BN]

Wow, $70 off the 3800X! I picked up mine at $50 off. Ooof

Go for it