64-bit PCI question

64-bit PCI question

Post by Dan Smit » Sat, 30 Jun 2001 21:45:26



I have 2 64-Bit PCI slots on my board.  Some 32-Bit cards fit in them
(the ones with the front notch), but others do not.  What's the deal?
What does the front notch signify?  Does that mean that the card that
fits is able to run at the 66Mhz speed or something?

\Thankx!

--Dan

 
 
 

64-bit PCI question

Post by John Edwar » Sun, 01 Jul 2001 02:38:32


I don't think so.  I filed a notch in the front of one of the 32 bit
slots and installed a 64 bit PCI card and everything seems to work OK.
 It's probably the card that determines if it will runn at 33 or 66.
YMMV

> I have 2 64-Bit PCI slots on my board.  Some 32-Bit cards fit in them
> (the ones with the front notch), but others do not.  What's the deal?
> What does the front notch signify?  Does that mean that the card that
> fits is able to run at the 66Mhz speed or something?

> \Thankx!

> --Dan


 
 
 

64-bit PCI question

Post by Eric P. McC » Sun, 01 Jul 2001 02:46:55



> I don't think so.  I filed a notch in the front of one of the 32 bit
> slots and installed a 64 bit PCI card and everything seems to work OK.
>  It's probably the card that determines if it will runn at 33 or 66.

I read some documentation from a motherboard about a similar-sounding
notch on the AGP Pro slot.  It's apparently a retention notch.  Some
cards have a clip of some sort that go around it or something (sorry,
there were no pictures and I can't visualize this), and some don't.
They said it's perfectly harmless and you can remove (?) it if you
want or have to.

I'm not recommending you physically alter your motherboard in any way:
I provide the above purely so the OP might have some ideas about where
to look.

--

  "Knowing that a lot of people across the world with Geocities sites
absolutely despise me is about the only thing that can add a positive
spin to this situation."  - Something Awful, 1/11/2001

 
 
 

64-bit PCI question

Post by Iwo Mergle » Wed, 04 Jul 2001 00:01:35



> I have 2 64-Bit PCI slots on my board.  Some 32-Bit cards fit in them
> (the ones with the front notch), but others do not.  What's the deal?
> What does the front notch signify?  Does that mean that the card that
> fits is able to run at the 66Mhz speed or something?

> \Thankx!

> --Dan

If you mean the one close to the metal clamp it indicates
a 3.3V Bus. Some cards have both notches, which means they
support 5V and 3.3V operation.

You might get away with cutting a notch to make a card fit
mechanically. It might even work. But you are asking for
trouble. It will fail when it can do the biggest damage :^)

Iwo

 
 
 

64-bit PCI question

Post by Lucius Chiaravigl » Thu, 05 Jul 2001 15:17:29



Quote:>I read some documentation from a motherboard about a similar-sounding
>notch on the AGP Pro slot.  It's apparently a retention notch.  Some
>cards have a clip of some sort that go around it or something (sorry,
>there were no pictures and I can't visualize this), and some don't.
>They said it's perfectly harmless and you can remove (?) it if you
>want or have to.

>I'm not recommending you physically alter your motherboard in any way:
>I provide the above purely so the OP might have some ideas about where
>to look.

        Are you sure the one on PCI isn't for voltage keying?  If you
remove this notch and have hardware that can tolerate the voltage other
than what it was keyed for, you will be lucky and have no problems, but
in other cases . . . .

--
Lucius Chiaraviglio

To get the exact address:                         ^^^^^^^^^^^^^^^^^
Replace indicated characters with common 4-letter word meaning the same thing
and remove underscores (Spambots of Doom, take that!).

 
 
 

64-bit PCI question

Post by Tomasz Koryck » Thu, 05 Jul 2001 15:27:26




> > I have 2 64-Bit PCI slots on my board.  Some 32-Bit cards fit in them
> > (the ones with the front notch), but others do not.  What's the deal?
> > What does the front notch signify?  Does that mean that the card that
> > fits is able to run at the 66Mhz speed or something?

> > \Thankx!

> > --Dan

> If you mean the one close to the metal clamp it indicates
> a 3.3V Bus. Some cards have both notches, which means they
> support 5V and 3.3V operation.

> You might get away with cutting a notch to make a card fit
> mechanically. It might even work. But you are asking for
> trouble. It will fail when it can do the biggest damage :^)

> Iwo

I fulle agree! Don't do it, Dan! Here is a picture, for everyone's
reference:
http://www.supermicro.com/images/Imag_Prod/840/PCI_Slots.JPG

The one slot that is not shown there is a 3.3V, 32-bit one - fairly
rare. That one has the rib on the left (in the picture) side. BTW, the
left in this picture is the back adge of the mobo, where You connect all
Your stuff to the cards.

  And yes, some 32-bit cards have both notches and adjust to the slot
voltage. Haven't seen a 64-bit card like that, yet - but then again, 5V,
64-bit PCI is not very popular.

 
 
 

64-bit PCI question

Post by Lucius Chiaravigl » Sun, 08 Jul 2001 18:07:51





>> > I have 2 64-Bit PCI slots on my board.  Some 32-Bit cards fit in them
>> > (the ones with the front notch), but others do not.  What's the deal?
>> > What does the front notch signify?  Does that mean that the card that
>> > fits is able to run at the 66Mhz speed or something?

>> If you mean the one close to the metal clamp it indicates
>> a 3.3V Bus. Some cards have both notches, which means they
>> support 5V and 3.3V operation.

>> You might get away with cutting a notch to make a card fit
>> mechanically. It might even work. But you are asking for
>> trouble. It will fail when it can do the biggest damage :^)

>I fulle agree! Don't do it, Dan! Here is a picture, for everyone's
>reference:
>http://www.supermicro.com/images/Imag_Prod/840/PCI_Slots.JPG

>The one slot that is not shown there is a 3.3V, 32-bit one - fairly
>rare. That one has the rib on the left (in the picture) side. BTW, the
>left in this picture is the back adge of the mobo, where You connect all
>Your stuff to the cards.

>  And yes, some 32-bit cards have both notches and adjust to the slot
>voltage. Haven't seen a 64-bit card like that, yet - but then again, 5V,
>64-bit PCI is not very popular.

        Also note that 66 MHz operation is always with V[IO] at 3.3 V (not
100% sure for desktop PCI, but it is for sure in the specifications for
CompactPCI).  That is (almost certainly) why no 64-bit 66 MHz PCI slot with
5.5 V V[IO] is shown.  64-bit 66 MHz PCI devices might be able to tolerate
5.5 V V[IO], but the specification only allows for them to do this at 33 MHz.

        For your reference:  I fried an old (and probably expensive at one
time) 5.5 V V[IO] 3U CompactPCI backplane video card by putting it in a
backplane with V[IO] wired for 3.3 V.  No smoke came out, but it mysteriously
did not work any more.  (This happened in the course of testing hardware
produced where I work for 3.3 V V[IO] compatibility -- I knew which of our
stuff to avoid, but this card was made by another vendor and had no
documentation.)

--
Lucius Chiaraviglio

To get the exact address:                         ^^^^^^^^^^^^^^^^^
Replace indicated characters with common 4-letter word meaning the same thing
and remove underscores (Spambots of Doom, take that!).

 
 
 

64-bit PCI question

Post by Scott Olso » Sat, 28 Jul 2001 02:24:51


Question:

     Can a card designed for 64-bit PCI run in a 32-bit slot?  I'm
interested in the 3Ware 7410 IDE-RAID card (because of it's ATA-100
support), but it's a 64-bit PCI card and my current motherboard only has
32-bit PCI slots.

                                Scott

 
 
 

64-bit PCI question

Post by Joshua Baker-LePai » Sat, 28 Jul 2001 04:56:52



>      Can a card designed for 64-bit PCI run in a 32-bit slot?  I'm
> interested in the 3Ware 7410 IDE-RAID card (because of it's ATA-100
> support), but it's a 64-bit PCI card and my current motherboard only has
> 32-bit PCI slots.

I was in the same situation and was told that, yes, 64bit PCI cards will
run just fine (in 32bit mode, of course) in 32-bit PCI slots.  From all
reports, the 3ware cards are supposed to pretty nice.

--
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University

 
 
 

64-bit PCI question

Post by B. Joshua Rose » Sat, 28 Jul 2001 12:00:48


The 3Ware cards will run fine in a 32 bit slot. I've been using 7810s in
both 64 bit and 32 bit slots.

Josh



> Question:

>      Can a card designed for 64-bit PCI run in a 32-bit slot?  I'm
> interested in the 3Ware 7410 IDE-RAID card (because of it's ATA-100
> support), but it's a 64-bit PCI card and my current motherboard only has
> 32-bit PCI slots.

>                            Scott