Question Zen 4 builders thread

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CP5670

Diamond Member
Jun 24, 2004
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Yeah, I have that same card and the radiator spews a huge amount of heat. It's like a mini space heater and makes the case's top panel too hot to touch. The CPU radiator would produce much less heat, so it's better as an intake.
 

lopri

Elite Member
Jul 27, 2002
13,173
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Those who have issue with S3, what is tREFI value of the non-sleeping setup? I can imagine too low a value being a problem. Also check if there is something labeld "DRAM Power Down" or something similar, and whether enabling/disabling it makes a difference.

trefi.PNGPD.png
 
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itsmydamnation

Platinum Member
Feb 6, 2011
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Even with DDR4 memory. Running tight timings Cas 14 or Cas 16 will smoke DDR4 3200mhz if you run Cas 16 at 3600mhz+. Yes tighter timings make sense but as the DDR5 memory matures. If 8000mhz sticks are cheap and readily available. 6000mhz DDR5 sticks with tight timings will not be able to compete with 8000mhz and above DDR5 regardless of their timings.

Tight timings cannot overcome bandwidth benefits with faster memory sticks. AMD said that Zen 4 would be an OCer's dream. Now I am heard DDR5 6400mhz is asking too much. Like Zen 3, it may just need a bios update. My original B350 motherboard runs DDR4 16-20-20-20 @ 3800mhz.

If the current Zen 4 motherboards can support DDR5 8000mhz with a bios update. Then people will have nothing to worry about. Otherwise we will have to listen to Intel fans talking about fast DDR5 (8000mhz) being for Intel builds only.

This is the only forum that is pro intel in such a way that they deny Raptor Lake being excellent. My only complaint about Intel is that I am waiting for the Intel 4 (7nm silicon). With the release of the 7900 @ 65w. I have no problems with AMD. Energy efficiency is something I value over top line performance. The AMD motherboard pricing gives me pause.
Zomg , you buy the 8000 memory and run at even tighter timings at 6000.
 
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itsmydamnation

Platinum Member
Feb 6, 2011
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But how low can timings go? Suppose I get DDR4-5000. Can I run it at DDR4-3600 CL10?

Or for that matter, can DDR5-6400 be run at DDR5-4800 CL20?
I assume DDR5 is the same as DDR3/4 in that really its all about access time in NS. so in its most simplest form clock * CAS .



so for example from above 6400 link @ CAS 32 should run fine at 6000 @ CAS 30. you will have less bandwidth but same latency.
 
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lopri

Elite Member
Jul 27, 2002
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Latency and bandwidth both are important. Try software (heck even hardware) decoding 4K video with DDR2, it is not fun.

I found this out of the blue, it seems clear that Infinity Fabric is what determines the upper memory bandwidth on Zen 4. (32B/cycle) Higher memory frequency is not going to be very useful unless IF is widened. Note IF also deals with PCIE directly via lclk. (64B/cycle, AMD prioritizes it over memory, I guess?)

x_SoC-topology-chiplets.png
 
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lopri

Elite Member
Jul 27, 2002
13,173
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I am not an engineer but the implication of the above may be: Restructuring the IF is a trade-off that AMD will have to think hard about before making. First, wider IF will eat into precious die area. Second, since it is part of silicon it has to be powered on to be useful, adding to total power budget. Third, it is likely a "fixed cost" that does not necessarily scale with performance. You have to keep the lights on whether there is a customer or not, or you might as well close shop.

See the disaster unfolding with RDNA3 and its idle/2D power consumption. Could it have been caused by unwise/untimely deployment of Infinity Fabric? Radeons also got this thing called "Infinity Cache" since RDNA2, but they made it smaller with RDNA 3 for whatever reason. So the GPU group went with chiplets (Infinity Fabric) while shrinking cache, and the result? is not very good, to say the least. Maybe it's a learning curve, or maybe it's incompetence. Thankfully on the CPU side AMD appears to be doubling down on 3D V-cache..
 

Justinus

Platinum Member
Oct 10, 2005
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Just updated to AGESA 1.0.0.4 (BIOS F8g for my X670E Aorus Master)

Same settings as the last time I posted this. Solid gains in read and write.

View attachment 73625

View attachment 73626

my score before the update with the same settings was ~6m 7s
Updated to F8h bios and it shaved off even more latency. Woot for incremental improvements.

One of these days I'll get around to actually tuning the timings.

1673983873428.png

Edit: LOL WHAT
1673984910766.png
Previous bios with same config is in quoted post, 5m44s
 
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Timmah!

Golden Member
Jul 24, 2010
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Yeah, I have that same card and the radiator spews a huge amount of heat. It's like a mini space heater and makes the case's top panel too hot to touch. The CPU radiator would produce much less heat, so it's better as an intake.
Eh, this sounds reasonable.

This kinda ruins my intention regarding aesthetics - now it was never going to be pretty due to mismatched GPUs, but i still wanted to salvage it with ARGB version of Arctic 420 up top. If i put the CPU rad to the front, then no point in RGB fans lol, since i chose FD 7XL version with solid front panel. Perhaps should have chosen Meshify 2XL then, was playing with that thought, but wanted 7XL more, since i like its looks more.

I presume keeping CPU rad up, but as an intake, and GPU one infront as exhaust is not the best idea? Or both as exhausts in those positions, and single back and 2 bottom 14cm fans as intakes? I realize the heated air goes up, but thats in natural condition - since this is forced air circulation, does that even matter?

EDIT:

https://www.reddit.com/r/watercooling/comments/w6i01g
here is claimed both rad as exhaust is the best? Though its custom loop situation, not 2x AIOs with another aircooled GPU on top.
 
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CP5670

Diamond Member
Jun 24, 2004
5,263
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That might work with just one card but I would think you need some air circulation inside for the other card. I only have that one GPU radiator and have all front fans as intakes.
 

AdamK47

Lifer
Oct 9, 1999
14,474
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What exactly is the CB R23 Performance Bias doing in the Asus BOIS?

1674054276899.png

I usually select None for Performance Bias since I have not seen it do anything until now. It seems to give a bit of memory performance @ DDR5 6000. Tried it earlier when I was using 6200 with much looser timings and it didn't show any impact. Now it does.

With CB R23:
1674054522253.png
1674054541183.png

Without CB R23:
1674054566013.png
1674054580756.png

Memory timings are the same for both:
1674054634033.png
 

Timmah!

Golden Member
Jul 24, 2010
1,172
364
136
That might work with just one card but I would think you need some air circulation inside for the other card. I only have that one GPU radiator and have all front fans as intakes.
Yeah, it seems to be impossible to solve. Either i make the one GPU rad as exhaust, but then it will be sucking in the air inside the case, that would be warmed up by the other air-cooled card, or i will make it as intake, which will then blow the hot air inside the case, making it worse for the air-cooled card. Catch 22 :)

I think i will be going with CPU 420 rad as intake then, since the CPU will produce less heat than GPU. Its 7950x and i may even run in one of the lower wattage modes, we shall see. Additionally, in situation when both GPUs would be rendering, CPU will be only lightly loaded, so there should not be blowing hot air inside the case when both gpus are under load.
The question remains whether i place the CPU rad up top or in the front (and then GPU rad as exhaust in the other position). Front would be probably better, but it will be waste of those rgb fans.

EDIT: Can i replace the stock fans on the GPU radiator for different, RGB ones? For example for 2 of these:


I think these are the same type that is mounted on Arctic Freezer AIOs, so should be good for rad. Not sure if better than the stock MSI ones though.

EDIT 2: OK, made 3 diagrams, help me pick the best one pls
 

Attachments

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lightmanek

Senior member
Feb 19, 2017
360
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What exactly is the CB R23 Performance Bias doing in the Asus BOIS?

View attachment 74856

I usually select None for Performance Bias since I have not seen it do anything until now. It seems to give a bit of memory performance @ DDR5 6000. Tried it earlier when I was using 6200 with much looser timings and it didn't show any impact. Now it does.

With CB R23:
View attachment 74857
View attachment 74858

Without CB R23:
View attachment 74859
View attachment 74860

Memory timings are the same for both:
View attachment 74861
In Zen 1 days it was tweaking L1/L2 cache latencies to match Zen+ as most Zen1 cores could do it apart from early samples. Not sure what it does for Zen4 but seems like it tweaks prefetchers.
 

q52

Member
Jan 18, 2023
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I am on Ryzen 3950X w/ 2x32GB 3200MHz DDR4 in an mITX build, at what point will it be worth it for me to upgrade? Of course performance improvements with 7950X look great but it would also require new RAM + motherboard (and I just re-built this one not even 6 months ago).
 

Saylick

Platinum Member
Sep 10, 2012
2,282
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EDIT 2: OK, made 3 diagrams, help me pick the best one pls
My 2c: Put the GPU rad at the front of the case as an intake, and the CPU rad at the top as an exhaust. Bottom two case fans are intake, rear case fan is exhaust.

As a gaming PC, you're going want the GPU to be fed with as much fresh air as possible. Cooling the 7950X with the freshest of air isn't worth it because Zen 4 clocks don't scale all that well with better cooling to begin with, i.e. even if you could improve the CPU's temps by 1C, you're likely not gaining much in sustained all core clock. Assuming you're playing at 4K, you should strive to be GPU limited anyways by cranking up all graphical settings.

EDIT: Wow, how did I miss the fact that you have not one but TWO 4090s?! And it's a rendering rig... *facepalms* Okay, I think that's a hint that I need some coffee. Yeah, in that situation I think you're kind of SOL. There's no perfectly optimal solution. The only advice I could offer is to keep the flow of air in one general direction, preferably one where hot air moves up, so I guess my above recommendation would still apply. I suspect the bottom 4090 is going to be more thermally limited in every situation.
 
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AdamK47

Lifer
Oct 9, 1999
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In Zen 1 days it was tweaking L1/L2 cache latencies to match Zen+ as most Zen1 cores could do it apart from early samples. Not sure what it does for Zen4 but seems like it tweaks prefetchers.
Whatever it's doing is minor. It's free performance so I'll take it. Passes stability testing.
 
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Chaotic42

Lifer
Jun 15, 2001
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I am on Ryzen 3950X w/ 2x32GB 3200MHz DDR4 in an mITX build, at what point will it be worth it for me to upgrade? Of course performance improvements with 7950X look great but it would also require new RAM + motherboard (and I just re-built this one not even 6 months ago).
I'd say you should upgrade when your computer can't do what you want it to do. I was thinking about upgrading my 9700K to a 7900X3D next month, but then I thought "why?". It works perfectly fine for the games I play, so I'm waiting until the 8000 series.

Unless you just want to upgrade for the fun of it :p
 

fleshconsumed

Diamond Member
Feb 21, 2002
6,399
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I am on Ryzen 3950X w/ 2x32GB 3200MHz DDR4 in an mITX build, at what point will it be worth it for me to upgrade? Of course performance improvements with 7950X look great but it would also require new RAM + motherboard (and I just re-built this one not even 6 months ago).
I was in the same position with 3950x, Zen4 looks mighty nice, but switching platforms is really expensive. Try to find a used 5950x maybe? If you're in the US check reddit r/hardwareswap, that's where I got my 5950x for $350, well worth it until AM5 platform matures/comes down in price.
 

In2Photos

Senior member
Mar 21, 2007
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I'm building a new Zen 4 PC - https://forums.anandtech.com/threads/new-build-finally.2609994/

I was planning to wait for the 7800X3D, but as we all know it won't be released until sometime next month. Am I crazy for thinking about getting a 7700X to use for now and then selling it when the 7800X3D comes in (assuming it's a good performer with good value)? I could then sell the 7700X or give it to my daughter and sell her 7600X.
 

igor_kavinski

Diamond Member
Jul 27, 2020
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I could then sell the 7700X or give it to my daughter and sell her 7600X.
If you think using the system for a month or two is worth the loss you might incur on selling used, sure, go ahead. It's also possible that the X3D is priced too high, in which case you may wanna wait even longer.
 

Justinus

Platinum Member
Oct 10, 2005
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I'm building a new Zen 4 PC - https://forums.anandtech.com/threads/new-build-finally.2609994/

I was planning to wait for the 7800X3D, but as we all know it won't be released until sometime next month. Am I crazy for thinking about getting a 7700X to use for now and then selling it when the 7800X3D comes in (assuming it's a good performer with good value)? I could then sell the 7700X or give it to my daughter and sell her 7600X.
I bought a 7950X to get my system up and running at launch intending to upgrade to a 7950X3D if they released one (whew, glad they are). I also bought 32GB of 6000C30 EXPO memory intending to upgrade when 64GB kits of the same spec came out.

You'll get nothing but support from me, 7700X is a smarter buy for temporary use than a 7950X. And of course, upgrade friend and family PCs whenever possible with hand-me-downs is how I roll. 7700X will last a bit longer with newer and newer games than a 7600X I'd think, although the 7600X is no slouch.
 

biostud

Lifer
Feb 27, 2003
17,104
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I bought a 7950X to get my system up and running at launch intending to upgrade to a 7950X3D if they released one (whew, glad they are). I also bought 32GB of 6000C30 EXPO memory intending to upgrade when 64GB kits of the same spec came out.

You'll get nothing but support from me, 7700X is a smarter buy for temporary use than a 7950X. And of course, upgrade friend and family PCs whenever possible with hand-me-downs is how I roll. 7700X will last a bit longer with newer and newer games than a 7600X I'd think, although the 7600X is no slouch.
The 7700 non X is an even better temporary CPU, as it also comes with a cooler for the next user.
 

Justinus

Platinum Member
Oct 10, 2005
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The 7700 non X is an even better temporary CPU, as it also comes with a cooler for the next user.
If it ends up going to his daughter, I'd think he knows exactly what the cooling setup in her PC is and what her use case is.

She's already got a 7600X so she likely has some kind of aftermarket cooler.
 
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