Latency mesage SOLVED !

tommylight wrote: Did you disable everything regarding power saving, speed step, hyperthreading, etc in BIOS?

The ZIP file contains all BIOS screen. Are all settings OK for Stepping ?

Everything seems fine, do some latency tests.

tommylight wrote:

macsddau@linuxcnc wrote: Is this the good link to start with RTAI ?
www.linuxcnc.org/iso/linuxcnc-2.7.14-wheezy.iso

Yes, but it is to old so there are no updates or support or well anything, as you can not install anything any more in it.
But if you have a simple machine, please do give it a try, it should work as is and has a much lower latency on older PC's.

Can’t boot with it. Is it live cd?

It has to be written to a USB using DD on Linux or win32diskimager on windows.

tommylight wrote: It has to be written to a USB using DD on Linux or win32diskimager on windows.

Yes I have already do this (dd).
I have downloaded it on my Mac then transfer it to the CNC computer with a USB key and after copy on the hdd write the iso to the same USB key.
Bios don’t show it for boot.

A good news
After some BIOS or grub adjustment and making a hard stress test a get a pretty good value for base thread.

I will get good feed fate for milling.

Finally this PC configuration is not so bad for stepping. I Will recommend it for is low cost side.
- ASRock J3355B-ITX : 69,95€
- WD Green SSD 120Go : 26,95€
- G.Skill SO-DIMM 4 Go DDR3L 1333 MHz CL9 : 21,75€
- Sapphire Radeon HD 6450 - 2 Go : 49,96€
Less than 200€ for the basic components, all new.

Today's result :

That looks really good.

Some questions ?
- If I move home directory on to an other drive, will I get less latency ?
- Same question if I replace ddr 1333 ram by one that have more speed?
- is it better to have one or two ram device?

No matter what you do will help, it is as good as it gets.
Memory has little effect on latency except when a memory module or memory controller is failing, HDD/SSD have effect on latency, sometimes a lot, power saving options and the south bridge on the main board have the most effect.
It is better to have 2 DIMM memories than one as it enables the dual channel memory use.