Generic CPU discussion

Ian&Steve C.
Ian&Steve C.
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Yes mine clicks. That’s how

Yes mine clicks. That’s how the tool is supposed to work. It’s pre-set to the correct torque. 

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Tom M
Tom M
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  Epyc Ram If you

 

Epyc Ram

If you assume memory speed and number of memory channels will have no effect on an epyc GPU server is this a good choice? It's cheap.

Tom M

A Proud member of the O.F.A.  (Old Farts Association).  Be well, do good work, and keep in touch.® (Garrison Keillor)  I want some more patience. RIGHT NOW!

Keith Myers
Keith Myers
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It's functional.  That is

It's functional.  That is about all you can say about it.  Your Epyc cpu will run at 2666, 2966 or 3200 Mhz depending on the generation.

And memory speed does impact calculations at all levels of course.  Slower memory = slower calculations no matter the processor.

You still have to shovel data between the cpu and the gpu and vice versa through main memory.

What cpu are you going to use?

 

Tom M
Tom M
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Keith Myers wrote: What cpu

Keith Myers wrote:

What cpu are you going to use?

My current plan is to use the first epyc I bought. A first gen 8c/16t one. I will have to look up the model. I am pretty sure it is limited to 2667? memory speed.

Maybe I should go for two sticks of 3200 which would lower the cost but allow me to add two more later. And or upgrade to a gen 2 epyc CPU with out paying for faster ram.

Tom M

A Proud member of the O.F.A.  (Old Farts Association).  Be well, do good work, and keep in touch.® (Garrison Keillor)  I want some more patience. RIGHT NOW!

Keith Myers
Keith Myers
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The 3200 memory will do

The 3200 memory will do nothing for your current processor.  It will be limited to 2400 Mhz if you have a 7251 model.

But, it might be the smarter decision if you are going to upgrade to a later processor.

However, and a big gotcha is the minimum number of sticks to use for Epyc is 4 sticks for balanced operation.

You only have two active dies with only half of the 8 cores of the CCD's activated.

With only two sticks, you would only be using 1 stick per die and the memory operation would not be at all efficient.  You really need to have at minimum 4 sticks so that each die gets two sticks for interleaving.

I would instead opt for a minimum of 4 sticks and for the 2400 Mhz speed.

Accept that you will need to upgrade to better memory if and when you decide to upgrade your cpu to a Epyc 7002 model.

 

Tom M
Tom M
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Can anyone find some $50 /

Can anyone find some $50 / stick 3200 MHz epyc memory?

A Proud member of the O.F.A.  (Old Farts Association).  Be well, do good work, and keep in touch.® (Garrison Keillor)  I want some more patience. RIGHT NOW!

Keith Myers
Keith Myers
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Tom M wrote:Can anyone find

Tom M wrote:

Can anyone find some $50 / stick 3200 MHz epyc memory?

Never going to happen.  The cheapest I ever found for RDIMM 3200 DDR4 was $75 a stick.  Good Samsung memory.

Looking at current prices, that memory has increased in price. Trending toward $100 a stick now.

[Edit]

If you are going to stick to a 7002 processor as the best that your board can handle, you are limited to 2933 Mhz speeds in synchronous mode.  The 3200 memory would run in asychronous mode.

Might be smart to limit yourself to 2933 Mhz memory.  Here is  2933 Mhz memory for a decent price for 4 sticks.

2933 DDR4 RDIMM 16GB $72.38 each for quantities of 4 or more

 

Tom M
Tom M
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I have been playing with my

I have been playing with my Asus b450-f strix motherboard and the 3950x cpu.  Trying to get it to run with less cpu voltage.

Here is the baseline with 4.125 GHz and "auto" cpu voltage.  OBTW, the LLC parameters are not very granular.

===snip===

tlgalenson@Moonglow-CPU:~$ sensors
k10temp-pci-00c3
Adapter: PCI adapter
Tctl:         +90.1°C  
Tdie:         +90.1°C  
Tccd1:        +89.5°C  
Tccd2:        +87.2°C  

nvme-pci-0100
Adapter: PCI adapter
Composite:    +55.9°C  (low  = -273.1°C, high = +84.8°C)
                       (crit = +84.8°C)
Sensor 1:     +55.9°C  (low  = -273.1°C, high = +65261.8°C)
Sensor 2:     +57.9°C  (low  = -273.1°C, high = +65261.8°C)

asuswmisensors-isa-0000
Adapter: ISA adapter
CPU Core Voltage:          1.35 V  
VPP MEM Voltage:           2.52 V  
+12V Voltage:             10.14 V  
+5V Voltage:               5.01 V  
3VSB Voltage:              3.31 V  
VBAT Voltage:              3.21 V  
AVCC3 Voltage:             3.33 V  
SB 1.05V Voltage:          1.04 V  
CPU Core Voltage:          0.00 V  
CPU SOC Voltage:           0.00 V  
CPU Fan:                 1418 RPM
Chassis Fan 1:              0 RPM
Chassis Fan 2:              0 RPM
Chassis Fan 3:              0 RPM
AIO Pump:                   0 RPM
Water Pump:                 0 RPM
CPU OPT:                 1484 RPM
CPU Temperature:          +87.0°C  
CPU Socket Temperature:   +41.0°C  
Motherboard Temperature:  +57.0°C  
Chipset Temperature:      +54.0°C  
Tsensor 1 Temperature:   +216.0°C  
CPU VRM Temperature:       +0.0°C  
CPU VRM Output Current:    0.00 A  

tlgalenson@Moonglow-CPU:~$

===snip===

I have been trying to drop the cpu voltage to something like 1.31 volts but it actually is registering out at about 1.29 volts.  I tried to use the LLC to handle the drooping.  But apparently even on LLC "high" it still locks up after a while.

I am reluctant to install my X570 MB just to get access to a more granular LLC parameter.

Any ideas?

Tom M

 

A Proud member of the O.F.A.  (Old Farts Association).  Be well, do good work, and keep in touch.® (Garrison Keillor)  I want some more patience. RIGHT NOW!

mikey
mikey
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is that your email address in

is that your email address in that stuff?

GWGeorge007
GWGeorge007
Joined: 8 Jan 18
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mikey wrote: is that your

mikey wrote:

is that your email address in that stuff?

No, it's his user name on his Moonglow computer via the terminal in Linux.

George

Proud member of the Old Farts Association

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