[SOLVED] Can slow speed RAM bottleck the whole system?

[Ayymd]

I had cheaped out a while ago on RAM and bought DDR4 16GB G.skill 1000MHz RAM. I have Ryzen 7 2700X and RTX 2070S ( I know those two wont bottleneck). But the question is if the RAM bottlecks the CPU someway. CPU Clock is boosted to 45.5x100 and GPU is base clock (8gb ddr6). I recall hearing from somewhere that the RAM speed is related to CPU speed. Also XMP and dual channel is on. Ive seen videos about 2133MHz vs 3000MHz vs ... etc and the FPS gap is quite big imo. Im wondering how big the gap would be with my speeds.

My questions are the following:

1. If it bottlenecks then how exactly?

2. Should I upgrade my RAM to better speeds?

3. If I am going to upgrade to better speeds then, whats the best speed to go for ( cheaping out wont be an option)

4. Does ananas go on pizza?

 

[dimtodim]

I had cheaped out a while ago on RAM and bought DDR4 16GB G.skill 1000MHz RAM. I have Ryzen 7 2700X and RTX 2070S ( I know those two wont bottleneck). But the question is if the RAM bottlecks the CPU someway. CPU Clock is boosted to 45.5x100 and GPU is base clock (8gb ddr6). I recall hearing from somewhere that the RAM speed is related to CPU speed. Also XMP and dual channel is on. Ive seen videos about 2133MHz vs 3000MHz vs ... etc and the FPS gap is quite big imo. Im wondering how big the gap would be with my speeds.

My questions are the following:

1. If it bottlenecks then how exactly?

2. Should I upgrade my RAM to better speeds?

3. If I am going to upgrade to better speeds then, whats the best speed to go for ( cheaping out wont be an option)

4. Does ananas go on pizza?

ryzen 9 3900x cant work on 45.5

 

[Ayymd]

ryzen 9 3900x cant work on 45.5

Sorry, typo 44,5 i have great cooling

 

[Darkbreeze]

Can slow speed RAM bottleck the whole system?

Yes, it certainly CAN, but we need some more accurate information because there are NOT any "1000mhz" DDR4 memory kits. Aside from a couple of early limited release products there is nothing below 2133mhz for DDR4.

RAM speed has nothing to do with CPU speed, although, a stronger CPU with a higher frequency and more voltage can certainly bolster the memory controller and ALLOW you to have a stable memory configuration with higher speed memory kits, in some cases. More important, usually, is the motherboard chipset type. This usually dictates what speed of memory can be run on a given configuration and it may or may not depend on which CPU is actually being used. Some CPU models, on a given chipset type, might be limited to lower speed memory, so in that way your statement would be true, but it's equally true that there are a number of systems out there where it makes no difference what CPU is in use.

For your system, it does, to a degree, dictate things, because your 2nd Gen Ryzen CPU is likely going to limit what speed of memory you can run.

What is your motherboard model and does it have the most current BIOS version installed?

 

[hotaru.hino]

AMD systems tie the CPU system bus (the Infinity Fabric) speed to memory speed, so the faster the memory speed you get, the better the system runs. AMD says that the 2700X supports up to DDR4-2933, which I would argue that's more like the bare minimum you should get to start. Anything less and RAM becomes the stumbling block. It doesn't hurt to go faster, but the system bus can only be clocked so high before it gets unstable, so the sweet spot for Ryzen 2000 is around DDR4-3200.

 

[Darkbreeze]

ryzen 9 3900x cant work on 45.5

Where did you see any mention of 3900x, because I don't see that?

 

[Darkbreeze]

AMD systems tie the CPU system bus (the Infinity Fabric) speed to memory speed, so the faster the memory speed you get, the better the system runs. AMD says that the 2700X supports up to DDR4-2933, which I would argue that's more like the bare minimum you should get to start. Anything less and RAM becomes the stumbling block. It doesn't hurt to go faster, but the system bus can only be clocked so high before it gets unstable, so the sweet spot for Ryzen 2000 is around DDR4-3200.

But, it's important to note that it will NOT run at 3200mhz on some board models and/or with some memory kits. You are a lot more likely to be ABLE to run them at 3200mhz with newer chipsets and specific, high quality memory kits. As I'm sure you know. Somebody with an A320 board and a very cheap memory kit is probably going to struggle, or not be able to run them at all, above 2933mhz, in a lot of cases. As just ONE example.

 

[Ayymd]

Yes, it certainly CAN, but we need some more accurate information because there are NOT any "1000mhz" DDR4 memory kits. Aside from a couple of early limited release products there is nothing below 2133mhz for DDR4.

RAM speed has nothing to do with CPU speed, although, a stronger CPU with a higher frequency and more voltage can certainly bolster the memory controller and ALLOW you to have a stable memory configuration with higher speed memory kits, in some cases. More important, usually, is the motherboard chipset type. This usually dictates what speed of memory can be run on a given configuration and it may or may not depend on which CPU is actually being used. Some CPU models, on a given chipset type, might be limited to lower speed memory, so in that way your statement would be true, but it's equally true that there are a number of systems out there where it makes no difference what CPU is in use.

For your system, it does, to a degree, dictate things, because your 2nd Gen Ryzen CPU is likely going to limit what speed of memory you can run.

What is your motherboard model and does it have the most current BIOS version installed?

I currently am not near to my PC, Ill get more info in 3 days. I have MSI b450 Tomahawk, yes latest bios is installed I havent studied so much about RAM but is ther actually no connection to those speeds?

 

[Ayymd]

AMD systems tie the CPU system bus (the Infinity Fabric) speed to memory speed, so the faster the memory speed you get, the better the system runs. AMD says that the 2700X supports up to DDR4-2933, which I would argue that's more like the bare minimum you should get to start. Anything less and RAM becomes the stumbling block. It doesn't hurt to go faster, but the system bus can only be clocked so high before it gets unstable, so the sweet spot for Ryzen 2000 is around DDR4-3200.

Would 3200+ be overkill or it wouldnt do any good at all?

 

[Ayymd]

But, it's important to note that it will NOT run at 3200mhz on some board models and/or with some memory kits. You are a lot more likely to be ABLE to run them at 3200mhz with newer chipsets and specific, high quality memory kits. As I'm sure you know. Somebody with an A320 board and a very cheap memory kit is probably going to struggle, or not be able to run them at all, above 2933mhz, in a lot of cases. As just ONE example.

Will a 4000MHz run on b450?

 

[hotaru.hino]

Would 3200+ be overkill or it wouldnt do any good at all?

It's not worth going past DDR4-3200

Will a 4000MHz run on b450?

It depends on the board. But if it's DDR4-4000, it's not worth it for a Ryzen 2700X

 

[Ayymd]

It's not worth going past DDR4-3200


It depends on the board. But if it's DDR4-4000, it's not worth it for a Ryzen 2700X

Okay, thank you for the answer!
Should i go for lower CAS Latency aswell or will there be a problem with that aswell

 

[hotaru.hino]

Okay, thank you for the answer!
Should i go for lower CAS Latency aswell or will there be a problem with that aswell

Go for the fastest speed your board can support, then the lowest CAS latency.

 

[Darkbreeze]

Actually, in the case of 4000mhz memory, I don't think it DOES matter what board you have. 2nd Gen Ryzen Pinnacle ridge isn't going to run at anything higher than 3600mhz on X570 or B450 chipsets, and many of these boards don't show support for anything higher than 3466mhz.

Besides which, once you cross the 3600mhz (In some cases, on 3rd Gen Ryzen, with a very good CPU sample and very high end memory, as well as a top notch motherboard, you MIGHT be able to hit 3733mhz and some very rare reports of hitting 3800mhz exist, but I am dubious because none of the reviewers seem to have been able to replicate this that I've seen) speed barrier the infinity fabric generally decouples from the 1:1 ratio and you suffer a latency penalty due to it automatically adjusting to a 1:2 ratio, meaning you have to run a kit significantly higher than 3600mhz to make it worthwhile or even break even. Plus, I'm not sure anybody has actually demonstrated any real gains by doing so. Probably there are SOME gains to be had, but they are probably worth neither the additional cost of getting hardware than can do it nor the extra work to make it happen.

For a 2700x on B450, I'd just look at getting a very good CL14 3200mhz 2 x8GB kit and call it a day. Keep in mind, a CL14 3200mhz kit has a lower True Latency than a CLd16 3600mhz kit, which means it is minimally faster, and while that probably won't translate into anything tangible in terms of performance, you may be able to pick up a kit for cheaper. If not, you can probably get a 3600mhz kit that's validated as compatible and if necessary reduce the speed and timings to tighten things up, if it's less expensive to do it that way. A 3600mhz kit dropped to 3466mhz and timings tightened down to CL14, would be pretty snappy indeed. It would take a pretty decent though to do that AND some additional work testing the stability.

I'd just say get a 3200mhz kit of whatever you can afford, make sure first that it IS compatible, and go with that. End of day, it's not going to make all THAT much difference anyhow, so long as you are above 2933mhz and don't have a very high latency kit.

 

[Ayymd]

Actually, in the case of 4000mhz memory, I don't think it DOES matter what board you have. 2nd Gen Ryzen Pinnacle ridge isn't going to run at anything higher than 3600mhz on X570 or B450 chipsets, and many of these boards don't show support for anything higher than 3466mhz.

Besides which, once you cross the 3600mhz (In some cases, on 3rd Gen Ryzen, with a very good CPU sample and very high end memory, as well as a top notch motherboard, you MIGHT be able to hit 3733mhz and some very rare reports of hitting 3800mhz exist, but I am dubious because none of the reviewers seem to have been able to replicate this that I've seen) speed barrier the infinity fabric generally decouples from the 1:1 ratio and you suffer a latency penalty due to it automatically adjusting to a 1:2 ratio, meaning you have to run a kit significantly higher than 3600mhz to make it worthwhile or even break even. Plus, I'm not sure anybody has actually demonstrated any real gains by doing so. Probably there are SOME gains to be had, but they are probably worth neither the additional cost of getting hardware than can do it nor the extra work to make it happen.

For a 2700x on B450, I'd just look at getting a very good CL14 3200mhz 2 x8GB kit and call it a day. Keep in mind, a CL14 3200mhz kit has a lower True Latency than a CLd16 3600mhz kit, which means it is minimally faster, and while that probably won't translate into anything tangible in terms of performance, you may be able to pick up a kit for cheaper. If not, you can probably get a 3600mhz kit that's validated as compatible and if necessary reduce the speed and timings to tighten things up, if it's less expensive to do it that way. A 3600mhz kit dropped to 3466mhz and timings tightened down to CL14, would be pretty snappy indeed. It would take a pretty decent though to do that AND some additional work testing the stability.

I'd just say get a 3200mhz kit of whatever you can afford, make sure first that it IS compatible, and go with that. End of day, it's not going to make all THAT much difference anyhow, so long as you are above 2933mhz and don't have a very high latency kit.

Hey, i got more info, here...

Memory-
Total memory slots 4
Used memory slots 2
Free memory slots 2
Type Unknown
Size 16384 MBytes
Channels # Dual
DRAM Frequency 1066.0 MHz
CAS# Latency (CL) 15 clocks
RAS# to CAS# Delay (tRCD) 15 clocks
RAS# Precharge (tRP) 15 clocks
Cycle Time (tRAS) 36 clocks
Bank Cycle Time (tRC) 51 clocks
Command Rate (CR) 1T
Motherboard-

Manufacturer Micro-Star International Co. Ltd
Model B450 TOMAHAWK (MS-7C02) (AM4)
Version 1.0
Chipset Vendor AMD
Chipset Model Ryzen SOC
Chipset Revision 00
Southbridge Vendor AMD
Southbridge Model B450
Southbridge Revision 51
System Temperature 35 °C
BIOS
Brand American Megatrends Inc.
Version 1.00
Date 02/07/2018
Voltage
VDDP 0.000 V
CPU CORE 1.448 V
DRAM 1.216 V
+12V 12.096 V
+5V 5.080 V
NB/SoC 1.184 V
+3.3V 3.344 V

 

[Darkbreeze]

So, "DRAM frequency 1066.0 Mhz" means you are running at the 2133mhz, which is the default JEDEC SPD for most DDR4 memory kits. I would definitely not be happy with are able to move to a faster kit. What would be MORE helpful is knowing what the ACTUAL model of your memory kit is, and you can find that by downloading and installing CPU-Z, then opening it and clicking on the SPD tab, then selecting a populated DIMM slot from the drop down menu on the upper left hand side of the window and then noting the model listed under the "part number" field.