Wait for DDR 5, or build a DDR 4 4000 Mhz system?

Soldato
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I'm finding that my current DDR 3 1600 Mhz RAM can't handle some games like WD: Legions well. I know it's RAM speed related, as similar older DDR 3 machines get similar results in this game and others. My PC dips to ~45 FPS regardless of the settings used.

So, what I'm wondering at the moment is:

1. Should I build a new DDR 4 system this year, and get 2x 8GB ~4000mhz RAM for about £100, and a cheap Rocket Lake motherboard and 11700/ 11700F Rocket Lake 8 core CPU?

OR

2. Wait until DDR 5 (probably 2022), and build a powerful Zen 4 based PC? I think Alder Lake will be available in Q1-Q2 2022, and Zen 4, Q3-Q4 2022.

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I have no idea how much DDR 5 RAM / motherboards will cost, and if DDR 5 will provide any tangible benefit vs high spec DDR 4 @ 4000 Mhz.

I recently brought a RTX 3070 FE and it's a bit of a beast for gaming, compared to my previous AMD R9 390, but it seems held back a bit by the slow DDR 3 RAM (maybe 4 core CPU too).
 
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Associate
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going by the move to ddr4 the first batch of ddr5 systems could be plagued with problems

personally building a rocket lake system in an Ideal world I want a 11700f as well but even a comet lake 10400f will run it really well

if you still have the r9 390 you might get nearly £200 for selling that to help fund
 
Soldato
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going by the move to ddr4 the first batch of ddr5 systems could be plagued with problems

personally building a rocket lake system in an Ideal world I want a 11700f as well but even a comet lake 10400f will run it really well

if you still have the r9 390 you might get nearly £200 for selling that to help fund
I stuck a 5800X in my B450 for now and will upgrade again come 2nd generation of DDR5 as any issues should be ironed by then and also speeds will have improved and hopefully prices dropped.

I'm finding that my current DDR 3 1600 Mhz RAM can't handle some games like WD: Legions well. I know it's RAM speed related, as similar older DDR 3 machines get similar results in this game and others. My PC dips to ~45 FPS regardless of the settings used.

I think WD is just a poorly optimised game as even my fps drops below 60 when driving around and that's on a 5800X with a 3080 @1440 RT on.
 
Soldato
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Caporegime
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History shows that the first examples of the next memory generation will be massively priced and usually run at slower MHz values than the previous gen. it’s possible the first DDR5 chips could be as ‘slow’ as 2666MHz and faster chips costing hundreds of pounds taking months to come along.
 
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Soldato
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Yes, I think this will be the lowest module speed.

It also uses the same 288 pins as DDR4.
It does look like they added some nice improvements and going with an AM5/LGA1700 would give you a better upgrade path in the future as current platforms are EOL but I guess it depends if you can wait.

Another option is to go for a B450 / B460 3600/10400F as a cheap upgrade for £300 to see you over for a year or two then jump again to the new gen stuff. Selling your current mob ram CPU would probably cover 70% of this upgrade.
 
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History shows that the first examples of the next memory generation will be massively priced and usually run at slower MHz values than the previous gen. it’s possible the first DDR5 chips could be as ‘slow’ as 2666MHz and faster chips costing hundreds of pounds taking months to come along.
Clock speeds are this time going to be higher than in DDR4.
Problem is Trump's **** insanely bad latencies:
https://www.tomshardware.com/news/chinese-vendor-launches-ddr5-4800-128gb-ram
That CL value would be same in absolute latency as using 2400MHz kit with CL20!
(while 18 clock pulse CL would be slow even at 50% faster 3200MHz)

Gotta wonder if AMD adds L4 cache into Zen 4's IO-die to mitigate effect of such absolutely craptacular latencies.
Release of Zen4 might also be moved until there are good latency kits available.

With separate IO-die already adding memory access latency compared to monolithic CPU just can't see AMD being able to afford such bad latencies.
(or gaming performance suffers)
Heck, that would no doubt hurt even Intel's monolithic CPUs, which aren't built around mitigating memory access latencies.
 
Soldato
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Clock speeds are this time going to be higher than in DDR4.
Problem is Trump's **** insanely bad latencies:
https://www.tomshardware.com/news/chinese-vendor-launches-ddr5-4800-128gb-ram
That CL value would be same in absolute latency as using 2400MHz kit with CL20!
(while 18 clock pulse CL would be slow even at 50% faster 3200MHz)

Gotta wonder if AMD adds L4 cache into Zen 4's IO-die to mitigate effect of such absolutely craptacular latencies.
Release of Zen4 might also be moved until there are good latency kits available.

With separate IO-die already adding memory access latency compared to monolithic CPU just can't see AMD being able to afford such bad latencies.
(or gaming performance suffers)
Heck, that would no doubt hurt even Intel's monolithic CPUs, which aren't built around mitigating memory access latencies.

I think games will require higher and higher RAM frequencies in the future. If 8000 mhz RAM is possible, I think the higher frequencies would (in most cases) more than make up for the longer latency times, compared to DDR4 4000mhz RAM. But, that would likely be very expensive.

There's also next gen CPUs to consider, that will likely be perform at least 20% better than Ryzen 5000 / Rocket Lake CPUs, due to IPC improvements.

I've heard that low RAM latencies can help with gaming, if playing at very high framerates, like 120/240. Personally, playing over 60 FPS doesn't interest me much...
 
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Soldato
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I did have 2400mhz ddr3 but had to drop to 1866 when it failed and Kingston said they only had 1866.

replaced it and got their fastest 64gb usb 3 as compensation then sold it for £60.

Not sure how much it’s hurting me. Haven’t really noticed as don’t play anything from before those days that I would likely notice (Arma/P3D etc).

I’d assumed I would have upgraded a long time ago but still at the point where I feel the gains won’t be worth the cash and I’ll be annoyed having just missed DDR4, missing out on DDR5
 
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You have a 4k monitor which the 3070 is going to struggle with in some games. 4k also often results in the game being gpu bound rather than cpu bound (if the cpu is decent). I wonder if you get some stutter from having a 4 core rather 6 core cpu. I doubt that you will see much, if any difference gaming at 4k, with ddr5 first gen cpu compared to the intel 11th gen or the current ryzen 5000 series. So I think the 11700f will be fine, especially as a new memory standard tends to be very expensive when they first come out. If you changed to a lower resolution then the cpu would matter more

https://youtu.be/AlfwXqODqp4?t=1177
 
Soldato
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Clock speeds are this time going to be higher than in DDR4.
Problem is Trump's **** insanely bad latencies:
https://www.tomshardware.com/news/chinese-vendor-launches-ddr5-4800-128gb-ram
That CL value would be same in absolute latency as using 2400MHz kit with CL20!
(while 18 clock pulse CL would be slow even at 50% faster 3200MHz)

Gotta wonder if AMD adds L4 cache into Zen 4's IO-die to mitigate effect of such absolutely craptacular latencies.
Release of Zen4 might also be moved until there are good latency kits available.

With separate IO-die already adding memory access latency compared to monolithic CPU just can't see AMD being able to afford such bad latencies.
(or gaming performance suffers)
Heck, that would no doubt hurt even Intel's monolithic CPUs, which aren't built around mitigating memory access latencies.
This Chinese stuff is probably aimed more for server/OEM markets, I'd imagen once the likes of Gskill TG and corsair bring out the gaming kits then it will have much better latency.
 
Soldato
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I think games will require higher and higher RAM frequencies in the future. If 8000 mhz RAM is possible, I think the higher frequencies would (in most cases) more than make up for the longer latency times
Gaming is really more latency time dependant than bandwidth dependant.
So more memory clock speed gives very limited/if any help when latency increases.
Because every time CPU core doesn't find needed data from registers or at the least cache, that's huge wait for execution of that thread in CPU's time scale.
(also lowering real world IPC from theoretical)

With CL18 kits available for 4000 MHz DDR4 it would take CL36 to have same absolute CAS latency for 8000 MHz.
While now existing DDR5 doesn't achieve that low clock pulse number even at lot slower clock speed with lot longer pulse time.
And when you crank up clock speed for same memory, latency in clock pulses increases to keep actual time same.
It would simply need lot faster DDR5 to match latencies achieved by DDR4.



This Chinese stuff is probably aimed more for server/OEM markets, I'd imagen once the likes of Gskill TG and corsair bring out the gaming kits then it will have much better latency.
DDR5 has been so long in development/making that when starting latencies are still such lousy, it might take some time before latencies can be squeezed to DDR4 level.
That would need lowering CL to below 25 at that 4800MHz.
 
Soldato
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According to this chart, the higher clock rates tend to mostly make up for the increase increase in latency, when running at higher CAS latencies, the difference at 2133mhz vs 5000mhz or higher being a few nanoseconds. E.g. 2133mhz at 7 CL = 6.56 ns, vs 5000mhz at 24 CL = 9.6 ns.

y10obfhbiaa31.png

From here:
https://www.reddit.com/r/overclocking/comments/cd4gme/ddr_effective_speed_based_on_frequency_and_cl/

If CL24 is becomes standard / common at higher frequencies than 5000mhz, the total latency should be 9.35ns or lower.

EDIT - although, for DDR5 4800 Mhz RAM, 34 CL might be the lowest latency available...
 
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Soldato
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Hopefully though, the increase in RAM frequency and CAS Latency will follow a linear progression, like DDR4 did, like this:

wWeUM82.png

It's possible the total latency won't be much more than 10-11ns for most DDR5 modules, if the CAS Latency is 25, 26, 27 or 28.

EDIT - Unfortunately though, it looks the CL latency increase won't increase linearly. Based on this AnandTech chart of JEDEC DDR5 standards, we can expect typical latencies of around ~14ns for the 'A' / lower CL modules:

DDR5-total-latency.png


That is, if the specification isn't changed by 2022.
 
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Associate
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Personally I'd upgrade now, it could be another 2 or 3 years before DDR5 based systems are reasonably priced and have any early problems figured out. As an early DDR4 adopter, I certainly wouldn't recommend buying the 1st available DDR5 motherboards and RAM modules.

Upgrade to DDR4 now and get a DDR5 system in 2023 or 24 when they're reasonably priced and show a bigger improvement over current gen RAM
 
Soldato
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Personally I'd upgrade now, it could be another 2 or 3 years before DDR5 based systems are reasonably priced and have any early problems figured out. As an early DDR4 adopter, I certainly wouldn't recommend buying the 1st available DDR5 motherboards and RAM modules.

Upgrade to DDR4 now and get a DDR5 system in 2023 or 24 when they're reasonably priced and show a bigger improvement over current gen RAM

Thanks, I'll certainly consider it in March / April. I'll probably buy the highest speed RAM I can afford.

I find the lack of response from AMD to the Rocket Lake launch a bit strange, perhaps they will simply lower their prices if needed.

The apparent higher latencies of DDR5 does make me doubt if there will be much performance gain - I think the main benefit will come from IPC gains from new CPU microarchitectures. I don't think PCIE 5 will matter to 99% of users.
 
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