"John McClane" said:
Hi!
I´m not even sure if there is such a board - but I´d like to eliminate some
bottlenecks on my 3rd machine ("download & MP3/DIVX-server"). Actually, this
system runs a PIII 750 at 1000 MHz on an Asus TUSL2-C. Extremely stable for
more than a year now. The only problem is the limited PCI bus bandwidth.
With a gigabit LAN-card and a Promise UDMA RAID controller it gives hell to
the 32 bit / 33 MHz PCI bus with its maximum 133 MB/s.
So I am looking for a cheap solution that offers more bandwidth there.
Unfortunately all socket 370 boards with 64 bit PCI bus I found are based on
ServerWorks chipsets and need fu... expensive registered DIMMs.
The A7M266-D can run up to 2 unregistered DIMMs but is an Athlon board.
Pretty difficult decision...
Anyone out there with a good idea in so far ???????
Thanx a billion in advance !
Cya -
Joachim
Get yourself a P4C800-E Deluxe, a Celeron, and a single stick
of slow DDR. The motherboard has a gigabit Ethernet interface
on a special CSA bus, so no PCI bandwidth is used.
If you download the ICH5R datasheet, for the other I/O devices on
the Southbridge, it says:
"Note that most transactions targeted to the ICH5 first appear
on the external PCI bus before being claimed back by the ICH5.
The exceptions are I/O cycles involving USB, IDE, SATA, and
AC ¹97. These transactions complete over the hub interface
without appearing on the external PCI bus."
I interpret this to mean, that storage devices plugged into the
SATA or IDE ports, are not restricted by PCI bandwidth concerns.
There are still bandwidth issues however - the IDE ports have
a max write speed of 88.9MB/sec and max read of 100MB/sec
(i.e. ATA100). The write speed is limited by a 22.5ns write
strobe chosen for the implementation (=44.4MHz x 16 bits).
As with any PCI bus, if you attempt to use your PCI disk
controller card, a practical limit of approx 100MB/sec still
exists, due to PCI overhead.
Note that the hub interface referred to above, and the CSA
interface, are each 266MB/sec interfaces. This means the built-in
gigabit Ethernet is independent of the storage, and the storage
has up to 266MB/sec minus however much the PCI bus is using at
any point in time. If you don't add any other PCI devices to the
board, then there should be more "breathing room" for what you want
to do.
There are some caveats with this board. In terms of feature set
versus operating system, I believe the fewest issues exist when
using WinXP. You can use IAAR35 RAID driver for the SATA interfaces
if you want. SATA RAID is not available with older Windows OSes.
If using a really old OS, like Win98se, it is possible that
plugging a disk into the SATA port, will result in a resource
conflict with the corresponding IDE port, and only one of the
two can be used at a time. I recommend doing a lot of reading of
reviews of the board, and also get datasheets on the Northbridge
and Southbridge of this board (i.e. 875 and ICH5R) from this page:
(Use the top two links on this page...)
http://developer.intel.com/design/chipsets/datashts/index.htm?iid=PCG+devleftnav&
If you are interested in building a full fledged server board,
the PC-DL is also an interesting product, and takes up to
two Xeon processors. You can read some of the interesting
hacking going on over on 2cpu.com, as people attempt to increase
the FSB and make a more powerful computing solution out of the
PC-DL.
******
As for your other suggestions, be wary of any server or non-server
board for that matter, offering multiple PCI busses. At least
one of the AMD chipsets has a bug, where the faster PCI bus
starves the slower PCI bus. I think I read over on 2cpu.com, that
the slow PCI bus in this case, is limited to 25MB/sec max transfer
rate under some conditions. This probably won't be a concern to you,
as you want two high speed slots.
I've also read this kind of comment for some other server board
designs, so again, a lot of research is required before buying a
multiple bus board, as there can be some expensive and rotten
surprises in store for you otherwise.
Have fun,
Paul
)
).