Trying to build dedicated hardware for LL testing - Poor performance

[Lasse]

Originally Posted by DrobinsonPE

I am currently running a similar setup

Gigabyte B365M DS3H, I7-9700K, four sticks of DDR-2666 4GB ram. The motherboard limits the ram to 2666.

Attached is a picture of my testing data for the CPU. It might be useful to you. You can save a lot of energy by decreasing the CPU clock without decreasing mprime throughput.

Wow that is a very interesting and informative spreadsheet.
My initial thought was to get a fast CPU to get fast speed but from your data it looks like that it's impossible to get enough memory bandwidth with normal hardware and one can pick a cheaper CPU and get the same performance.

[DrobinsonPE]

I have an i3-9100 and posted a picture of the same spreadsheet data for it in the CPU Efficiency thread. If I remember correctly, it was about 20% slower than the i7-9700.

Please post your results with the Z390 motherboard and the 3600 ram. If your throughput is significantly higher than mine, I might be tempted to upgrade again.

[Lasse]

First i tried the new RAM with the Asus H370-PRO Gaming motherboard.
For some reason the RAM was only at 2133MHz and it's very clear that I hit the memory bandwidth limit at around 2000MHz on the CPU.

Then i tried with the new Z390-M motherboard. RAM is running at the full 3600MHz and it looks like the CPU is now the bottleneck.
As you can see i have only tested a few CPU frequencys but it give some indications about how well it's doing. It's now at 4.981ms/ittr for the 103M exponent.

I'm not really sure why the CPU frequency goes much higher on the Z390-M motherboard compare to the H370-PRO.



I have ordered a better CPU cooler to see if i can push the CPU a little more.
Tomorrow i will also get my hands on a watt meter to get more data into the spreadsheet.


Will share when tests are done.

[axn]

Nice.

If 2133 RAM feeds CPU @ 2000 Mhz, linear scaling suggests 3600 RAM will support CPU @ 3400 MHz.

BTW, on the H370 mobo, is there any option available for enabling XMP?

[Lasse]

Originally Posted by axn

Nice.

If 2133 RAM feeds CPU @ 2000 Mhz, linear scaling suggests 3600 RAM will support CPU @ 3400 MHz.

BTW, on the H370 mobo, is there any option available for enabling XMP?

Sorry i did not bother to check the XMP settings. That would most likely have allowed the RAM to run with 2666 MHz as this is the upper limit for the H370 motherboard.

[DrobinsonPE]

Originally Posted by Lasse

Then i tried with the new Z390-M motherboard. RAM is running at the full 3600MHz and it looks like the CPU is now the bottleneck.
As you can see i have only tested a few CPU frequencys but it give some indications about how well it's doing. It's now at 4.981ms/ittr for the 103M exponent.

Will share when tests are done.

Please do share! Your 7.7ms/ittr with the H370 and 2133MHz ram is in the same ballpark as the 7.1ms/ittr I got with a B365 and 2666MHz ram. That is a significant speed up of mprime with the faster memory and the Z390. I might have to start looking for an inexpensive, refurbished or used Z390 motherboard and some faster RAM.

[Lasse]

Looks like I'm still hitting the bandwidth limit of the RAM when the CPU is running at around 3GHz.


Over the next coming days i will try to overclock the RAM.