Memory questions...

[Wanthuyr Filho 83]

It would be interesting seeing a real benchmarking with different RAM (and same everything else) in the P3D v4 world.

 

[lownslo 592]

2 hours ago, w6kd said:

Not sure I follow here...the difference between cutting-edge 8.25ns RAM and average 10ns RAM is 17.5%...not close together at all when related to the CPU speed.  A 5GHz CPU will tick through almost 9 additional idle clock cycles waiting for data with the average RAM vs the high-end stuff.

Does it make a difference?  It sure seems to, especially in areas of dense autogen and/or photoscenery (think ORBX SoCal).  When you see performance hits like dropping frame rate and/or stutters, yet neither the CPU nor GPU are close to maxxed out when it's happening, I believe that limited memory bandwidth is the culprit in that situation.

Regards

 

QFT!

[lownslo 592]

31 minutes ago, Wanthuyr Filho said:

It would be interesting seeing a real benchmarking with different RAM (and same everything else) in the P3D v4 world.

 

Paging FunknNasty, paging FunnNasty about memory tests...

Greg

[diajohn 165]

Sorry about lack of clarity.  I wanted to know if anyone could say that faster ram actually makes a user detectable difference with other components being equal, in P3D.  Usually a RAM change is done with other components this blurring the equation.

 

John

[fghdgdfdfgfgf 111]

2 hours ago, lownslo said:

Paging FunknNasty, paging FunnNasty about memory tests...

Greg

Answering page ....

I will try to put up some entertaining graphics on the subject tomorrow .....And I wonder why no one wants to talk memory. 🙂

-I installed an 8086 and 4400 mems today ...the good bad and ugly

[Cruachan 705]

14 hours ago, diajohn said:

Sorry about lack of clarity.  I wanted to know if anyone could say that faster ram actually makes a user detectable difference with other components being equal, in P3D.  Usually a RAM change is done with other components this blurring the equation.

 

John

Hi John,

I believe this article helps to put things into proper perspective:

https://www.velocitymicro.com/blog/important-ram-speed/

Edit: although Prepar3D may be a special case in the way CPU cache, VRAM and System memory all  interact for best performance.

Regards,

Mike

 

Edited January 22, 2019 by Cruachan

[fghdgdfdfgfgf 111]

 Cheers!

Edited January 22, 2019 by FunknNasty

[Cruachan 705]

3 minutes ago, FunknNasty said:

Proper perspective?

That's showing some real appreciation for the guys behind P3D, don't you think? I mean that two paragraph artical says nothing about how Prepared compares to Grand Theft Auto ....or did I miss something.  Your post gets a 'C'mon man!' 🙂

He, he, I was typing my edit as you posted your response! However, that article does still have some validity...only my opinion, of course!

Mike

[Bob Scott 7,720]

1 hour ago, Cruachan said:

Hi John,

I believe this article helps to put things into proper perspective:

https://www.velocitymicro.com/blog/important-ram-speed/

Yikes...this article does not reflect an in-depth understanding of system operation.

First, the article says that the RAM frequency is "the number of commands it (the RAM) can process per second."  Absolutely NOT.  The frequency is the number of clock ticks per second (from the IMC).  It is the pacing mechanism used by the memory module...but the memory does not execute a "command" each tick, but instead steps forward in the process of reading or writing data to RAM.  On one tick the memory might receive the read command, then the next tick it might set the data ready line to a false state, then it might wait 10 or more ticks for the data to stabilize on the bus, then it sets the data ready line to a true state, etc.  The total number of ticks needed to go from a memory request to completing that request is the CAS latency.  This is, of course a simplified example, but the characterization in this article of RAM frequency as a command rate is...wrong.

Then, in an even more glaring misstatement, the author says "system RAM will largely not be used when gaming."  This is patently wrong...system RAM is used for virtually every process running on a computer.

Since the background discussion in this article is so far gone, I can't with good conscience even consider the conclusions they draw as anything but flawed.

Regards

 

[fghdgdfdfgfgf 111]

No 'c'mon man' award for you then...

Sorry to have to do this to you Mike, but after reading Bob's post you’re going to have re-accept the 'c'mon man' award ..... sorry man, All in good fun, of course.

 

Edited January 22, 2019 by FunknNasty

[Cruachan 705]

1 hour ago, FunknNasty said:

No 'c'mon man' award for you then.... 🙂

Hi Ken,

Awe, shame! 😥 It would seem my contributions are exposing some deficiencies in my understandings of matters memory. Fair enough. On a more positive note, this stimulation of some educative reactions is to be welcomed 👍

I wonder how relevant standard benchmarking procedures are as applied to changes in performance in repeatable flight scenarios in Prepar3D?

Edit: Loading times at a complex hub, for example?

Regards,

Mike

 

 

Edited January 22, 2019 by Cruachan

[fghdgdfdfgfgf 111]

1 hour ago, Cruachan said:

Hi Ken,

Awe, shame! 😥 It would seem my contributions are exposing some deficiencies in my understandings of matters memory. Fair enough. On a more positive note, this stimulation of some educative reactions is to be welcomed 👍

I wonder how relevant standard benchmarking procedures are as applied to changes in performance in repeatable flight scenarios in Prepar3D?

Regards,

Mike

 

 

Well ,,, don’t know I have a meaningful answer to that, outside of my own experience with P3d and my hardware. I was sold on the importance memory and p3d with a test I did last spring at lax. Long story short I saw 10% boost in FPS going from 3200 c14 with XMP memory timings to 4133  using a bios memory preset.

 

buried deep in recesses of the  ROG forums is a 4400 vs 4133 bench post from a user that breaks down the memory universe to the sub atomic scale.

https://rog.asus.com/forum/showthread.php?101819-DDR4-4400-vs-4133

bare in mind this is an apple to apple comparison that really splits hairs. after reading it try to imagine the performance difference between a system like mine and another user with an 8700k running 2660 MHz c16.

Take the pi score bench time delta from slowest to fastest, a nearly two seconds difference,  Now imagine applying that to p3d .....2 second is 60 frames lost if running at 30 fps.

Edited January 22, 2019 by FunknNasty
Changed sub atomic ''level'' to scale