Is PCI-X the same as 64-bit, 66 MHz PCI?

I haven't been following PCI developments too closely. It __seems
that__ the two are identical, but perhaps not. I have already RTF web
sites.

Can anyone enlighten me.

maggie

On Sun, 28 Aug 2005 16:12:22 -0700, Lady Margaret Thatcher
wrote:

I haven't been following PCI developments too closely. It __seems
that__ the two are identical, but perhaps not. I have already RTF web
sites.

Can anyone enlighten me.

Regardless of the operating frequency, PCI-X Mode 1 uses a slightly different
bus-level protocol than PCI (all signals get a full bus tick to make
transfers, no need for "sneak clocks" in the io ring to make timing back to
the bus from hot-off-the-bus inputs).

The comparitively rare PCI-X Mode 2 is quite different electrically; PCI-X
Mode 1 and PCI use single-ended signaling while PCI-X Mode 2 uses differential
signaling, includes ECC at the bus level and is more packet oriented...

/daytripper

On Sun, 28 Aug 2005 19:28:28 -0400, daytripper
wrote:

On Sun, 28 Aug 2005 16:12:22 -0700, Lady Margaret Thatcher
wrote:

I haven't been following PCI developments too closely. It __seems
that__ the two are identical, but perhaps not. I have already RTF web
sites.

Can anyone enlighten me.

Regardless of the operating frequency, PCI-X Mode 1 uses a slightly different
bus-level protocol than PCI (all signals get a full bus tick to make
transfers, no need for "sneak clocks" in the io ring to make timing back to
the bus from hot-off-the-bus inputs).

The comparitively rare PCI-X Mode 2 is quite different electrically; PCI-X
Mode 1 and PCI use single-ended signaling while PCI-X Mode 2 uses differential
signaling, includes ECC at the bus level and is more packet oriented...

/daytripper

Thanks. I guess my next question is:

If I have a motherboard with 64-bit wide PCI slots, but without any
mention of PCI-X in its specs, can I use a PCI-X board in this
motherboard? The motherboard is an ASUS A7M-266D.

Thanks.

Lady Margaret Thatcher wrote:

On Sun, 28 Aug 2005 19:28:28 -0400, daytripper
wrote:

On Sun, 28 Aug 2005 16:12:22 -0700, Lady Margaret Thatcher
wrote:

I haven't been following PCI developments too closely. It __seems
that__ the two are identical, but perhaps not. I have already RTF web
sites.

Can anyone enlighten me.

Regardless of the operating frequency, PCI-X Mode 1 uses a slightly
different bus-level protocol than PCI (all signals get a full bus tick to
make transfers, no need for "sneak clocks" in the io ring to make timing
back to the bus from hot-off-the-bus inputs).

The comparitively rare PCI-X Mode 2 is quite different electrically; PCI-X
Mode 1 and PCI use single-ended signaling while PCI-X Mode 2 uses
differential signaling, includes ECC at the bus level and is more packet
oriented...

/daytripper

Thanks. I guess my next question is:

If I have a motherboard with 64-bit wide PCI slots, but without any
mention of PCI-X in its specs, can I use a PCI-X board in this
motherboard? The motherboard is an ASUS A7M-266D.

Your board uses the AMD-768 chip, which supports PCI 2.2. PCI-X is
_supposed_ to be backward compatible with PCI 2.2 so PCI-X boards _should_
work fine. What _should_ happen and what _does_ happen are not always the
same, but in general PCI-X boards should work

Thanks.

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)