What's the best Irq for G400

[jackzod]

I've read in a few comment that g400 is better on IRQ 9 and higher, what happen at other IRQ, presently I'm at IRQ 3 and doesn't seem to have any problem. Is it performance related or for stability?
just wondering.

Thanks

------------------
THIS SPACE FOR RENT

[Elie]

I recall Matrox always used to suggest IRQ 11, from experience it always worked for me with no conflicts at all. am I right Haig?

Regards,
Elie

[Wombat]

Yes, 9 or higher is suggested, more important for stability, but can effect performance ever-so-slightly as well.
What kind of hardware are you running? I've read about a number of Athlon owners whose G400 ends up on lower interrupts, but it hasn't caused any problems for them.

[bobby2]

Ive got an Abit BE6 and my G400 runs fine on both 3 and 9!

But how the hell do you get it to go to 9 and stay there?

bert

[Buuri]

But if it works with 3 isn't it better than 9-n considering the performace, while IRQ 3 is on a higher priority?

_
B

[This message has been edited by Buuri (edited 08 January 2000).]

[jackzod]

Hi here is my hardware
Abit Bh6 rev 1.01 (no I won't be able to use copermine d***it), cel 400@500, 128 meg ,
Motorola Cable modem, SB LIVE.
I Am now on Irq 3 because I have no modem and the mouse is P/s 2, so I've disabled the two Com port and it freed those two IRQ (3 and 4). I thought that the lower the IRQ the better for the Video card, presently I have no stability problem, so I was wondering if the issue was performance related.

To Bobby 2, to have your agp slot with a specific IRQ, you have to force an IRQ to the first PCI slot ( you find this in option in the BIOS), the AGP slot will take this IRQ, at least on a BH6.

------------------
THIS SPACE FOR RENT

[This message has been edited by jackzod (edited 08 January 2000).]

[birdy]

The higher the irq the better the performance (supposedly) The motherboard/os/cpu/whatever gives a higher priority to the higher irqs which is why you get the ide ports on 14 & 15 and i think other imporant motherboard stuff goes on 12 & 13. 11 is the best for the g400. The difference will not be noticeable however so if it's working fine then leave asi is.

------------------
p3 450@600. bx6 ver 2. 128mb unbranded pc100. iwill 2930u scsi, diamond pro pci modem, advansys 1505 isa scsi, SB Live!, pioneer dvd103s, hollywood plus dvd card, plextor 40x cd rom, ricoh 1420 cdr, ibm 13.5gb @ 7200rpm, G400 @ max settings. All wrapped up in a big case with loads of fans. Belinea 10 30 40 17" monitor

[Kruzin]

No, Buuri...IRQ 3 is a very low priority IRQ. 1,2,9-15,3-8 is the order of priority.
There is also the level/edge activation aspect of setting up the IRQs.

But, like has been said, if it works on IRQ3 for you, fine...leave it. But if there are issues, IRQs are always the first thing to look into.

[This message has been edited by Kruzin (edited 08 January 2000).]

[Gurm]

Darnit, Kruzin beat me to it.

IRQ's 9-15 are both Level Activated and higher in the ring processing order than the other IRQ's.

And actually, 0 and 1 aren't higher in priority than 9-15, believe it or not. It's pretty much a 0-7, 8-15 thing. I'll leave it to you "power-of-two" mathematicians to work that one out...

-Gurm

------------------
Listen up, you primitive screwheads! See this? This is my BOOMSTICK! Etc. etc.

[dneal]

My G400 has always been on IRQ 5. I have no problems but am curious, what's the best way to get it to a higher IRQ?

There are no cards in the two PCI slots below the AGP. Only PCI cards I have are SBLive and 3Com Fast Etherlink XL.


------------------
ABIT BH6 rev 1.0, Pentium III SL35D 450MHz -> 558MHz, 192MB SDRAM @ 124MHz CAS2, Toshiba 6X DVD,
Matrox Millenium G400 DH @ 160/200, Creative SBLive Value, 3Com Fast Etherlink XL PCI
Supermicro SC701A ATX 300watt TurboCool PC Power & Cooling PS, Panasonic Panasync S17

[Hairy Ogre]

Here is a bit of information from "The IRQ Book" by Kate Chase which gives a very good understanding of IRQ's, DMA's and I/O ranges. I highly recommend this book.

IRQ - Priority Level
0 - 1
1 - 2
2 - Not assigned - bridge to IRQ's 8-15
3 - 11*
4 - 12*
5 - 13*
6 - 14*
7 - 15*
8 - 3
9 - 4**
10 - 5**
11 - 6**
12 - 7**
13 - 8
14 - 9**
15 - 10**

* Can be used with 8-bit or 16-bit devices.
** Requires 16-bit devices only.