New computer for linuxcnc

What PC setup do you guys suggest?

This are my restriction:

if Mini-itx must have parallel port, so new one are totally out of question i think.

Good latency less than 15000, it would be a dream if less than 5000.

normal motherboatd ITX with 2 pci-e at least, and i think that's not a problem.

so i have some questions,

should i go amd or intel?

any motherboard and CPU in mind 2010-2013?

i can bouild the PC part by part, i just need some suggestion, i think ram 2 or 4 gigs should be fine, and a normal hard disk too.

what i'm really missing is a new motherboard and CPU with low latency and either 1 parport and one PCI, or 2 PCI.

Hi

This question comes up regularly in various guises

www.linuxcnc.org/index.php/english/forum...ns-tiny-pc-wpci-slot

This covers the classic D525 and some ASUS and other equivilents which are supposed to be better

regards

yes i did read that topic already and was opting for the ASUS E45M1-M PRO

unfortunatly the motherboard life cycle is so short, we will have to be searching for a new one pretty soon

unfortunatly the motherboard life cycle is so short, we will have to be searching for a new one pretty soon

Yes, then when they replace the board, they 'upgrade' it with a closed source video chip or similar and ruin it.

You should find you will be able to run across a broader range of hardware soon.

The testing version of linuxcnc, enabled for various flavours of real time is going well.
I am currently running Wheezy with a Debian stock rt-preempt kernel and have a homebrew 3.5.7-rtai kernel that will run 20K base and servo threads on a quad core machine 'as is'.

Before long there should be realtime kernels of various flavours available, which will handle the newest chipsets and a version of Linuxcnc which will run across them all.

Not that this will make 'old' boards like the D525 redundant.
I have 2 P4 machines in the workshop which return 9K base thread day in day out. As I have a spare in the loft and the same machines are still on Ebay for £30, I can't see me changing soon!

regards

I tested a friend PC this morning, it had pretty low letancy, i put the PC under some stress and it kept up with the latency test.

It had a Intel Processor G850

it was working on a motherboard H61M-P31 from MSI, which has only one PCI and no serial port

but i have found the H61M-P32 to have a serial port and a PCI.

Then i kept looking and i found a lot of H61 based motherboards, the price for buying the CPU and the motherboard separated is around twice as much as the D525.

but you have 2.9GHZ computer with better graphics, which is good if you need to run some CAD on the PC.

anyway i'm looking at the GA-H61M-S2P from Gigabyte, i'll let you guys know if i get good latency.

i found the Processor G850 to be with extended life by intel, so it's a good thing, i hope the motherboard change won't influence the latency.

i also saw the intel DH61WW motherboard, and i think it could have good latency, if anyone is willing to test.

I only run the latency test for around 5 minutes, but there was a lot of stress i think it could work.

I'll do extensive tests on the GA-H61M-S2P when i get it and let you know.

New PC tested and it has good latency with some tweaks.

After the tweaks when if i only open the test and nothing else and keep it going for an hour or so i get around 1000uS base thread max jitter, then moving stuff open a few glxgears, draftsight firefox all working at the same time for 20 minutes, and i get around 5000uS on max jitter Servo thread and 8000uS max jitter Base thread, sweet.

I did an over stressing test with burnP5, and glxgears opened in a big window, which make both cores at 100%, and the most i got was around 12000 max jitter on base thread. which i think is excellent for a worst case scenario.

So i think the results are nice, let's talk about the tweaks, i have SMI active, i still haven't try to disable it, i disabled isolcpu, so i'm working with both CPU.

At first i was getting 18000uS max jitter on base thread with normal use, then i went on the bios and disable everything possible on advanced CPU control, and that did the trick, now my worstest case scenario is 12000uS, which i think will probably never happen to have both CPU at 100% when working only on linuxcnc.


the computer is custom build with this parts.

CPU intel G860 3Ghz dual core
4GB RAM DDR3 1333Mhz on a single stick
H61M-S2PH Gigabyte motherboard, it's a Micro ATX, which is just a portion bigger of the Mini ITX like the 525 and 945 from intel, and it's sitting in the same box i had for the Mini ITX, i just have more PCI now, which is sweet i can get 5 parports on this thing if i wanted!

i'm cooling the CPU with the standard CPU cooler. i'll see if that is enough to keep it cold, i did disable all default cooling features from bios, right now it's a good time to test because where i'm staying it's 40 Degrees celsius!

motherboard+CPU are probably twice as much as the 525 was, but really it's a good trade for me, everything in the system is so much snappier, installations, opening programs.

And CPU and motherboards are easier to find right now, and i think the H61 chipset is going to keep going for sometime, and for what i have seen they all look pretty good with linuxcnc, i mean i was looking at an MSI motherboard with a G850 CPU, i bought a gigabyte motherboard with the G860 and it's looking just as good.

Draftsight wich i use a lot to design the stuff i'm going to cut, is still a bit laggy (i think the drivers for the intel integrated graphic on ubuntu 10.04 are not the best, even a big glxgear cannot round smooth), i'd say it's the same experience as with the 525 and 945 boards, I'd like to add a small graphic card with VGA that doesn't bother the CPU too much any suggestions?

can anyone upload this results to the wiki, or explain me how to do it?

Sounds good, nice to know another modern board has usable latency.

Anyone can edit a wiki, go to the bottom and there are some links right at the bottom left
One of them is something like Options, trouble is I see an item called Edit this page in its place so can't remember exactly what it was.
It just requires you to create a password etc and you can begin editing. It sets a cookie too, so you don't normally have to log in again.

This explains the editing format, but easiest thing to do is cut and paste another entry and change the details to suit
www.linuxcnc.org/index.php/english/forum...linuxcnc/reply/37778

If you get stuck I can do it for you tomorrow, but have a go

regards

I wrote my results in the Wiki

Any advice on a cheap graphic card that will not ruin the latency?

Any advice on a cheap graphic card that will not ruin the latency?

What did you use for the latency test?

If it has an on-board video chipset and those are the results, just carry on using that.

I use the on-board video on all my machines and have no problems, just need to have ample RAM, which you do.

regards

Well i was searching for a better PC because on the same PC i like to run draftsight, linuxcnc and a CAM of my coding all at the same time, right now i just have slow downs in drafsight, i think that is because the CPU integrated graphic don't support 3D acceleration, and because draftsight is not really coded well graphically...

So i bought an ATI HD 2400 a 512MB video card with 2 VGA for 20 dollars, i'm going to test it when it arrives, probably tomorrow.

I choose the 2400 HD because i was looking at a similar setup on the wiki latency test results (ASRock H61M-HVS with intel Celeron G530), and the guy seems to have good latency with this graphic card installed, so i'll give it a shot, if i'm able to run everything off the same PC with smooth performance it's really a few step forward for me.