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SCSI 64bit across a 32bit bus

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June 4, 2002 8:31:35 PM

Anyone know how much you would lose running a 64bit SCSI card on a 32bit board.

More about : scsi 64bit 32bit bus

June 4, 2002 11:57:01 PM

Here is a decent article to read up on: <A HREF="http://www.adaptec.com/worldwide/product/markeditorial...." target="_new">PCI 64 bit SCSI</A>

Since the burst rate of data throughput on the PCI bus doubles with 64-bit data transfers, it seems that you would lose half the throughput on a 32 bit PCI slot with a 64 bit card. Why would you want to do that? Plus I'm not sure if there are any adapters for that purpose. The 64 bit cards are long and I really don't think you could do this setup.

Here is your answer >>>>><A HREF="http://ask.adaptec.com/cgi-bin/adaptec_tic.cfg/php/endu...*dzZpSgg&p_lva=&p_faqid=3475&p_created=1007341233&p_sp=cF9ncmlkc29ydD0mcF9yb3dfY250PTE1JnBfc2VhcmNoX3RleHQ9NjQgYml0IHZlcnN1cyAzMiBiaXQmcF9zZWFyY2hfdHlwZT0zJnBfcHJvZF9sdmwxPTY2JnBfcHJvZF9sdmwyPTY5JnBfY2F0X2x2bDE9fmFueX4mcF9zb3J0X2J5PWRmbHQmcF9wYWdlPTE*&p_li=" target="_new">click here</A> or <A HREF="http://ask.adaptec.com/cgi-bin/adaptec_tic.cfg/php/endu...*dzZpSgg&p_lva=3475&p_faqid=1093&p_created=949614345&p_sp=cF9ncmlkc29ydD0mcF9yb3dfY250PTE1JnBfc2VhcmNoX3RleHQ9NjQgYml0IHZlcnN1cyAzMiBiaXQmcF9zZWFyY2hfdHlwZT0zJnBfcHJvZF9sdmwxPTY2JnBfcHJvZF9sdmwyPTY5JnBfY2F0X2x2bDE9fmFueX4mcF9zb3J0X2J5PWRmbHQmcF9wYWdlPTE*&p_li=" target="_new">here</A>

<font color=purple><b>An average human brain weights aprox. 3lbs., but a thought weights a load.</font color=purple></b><P ID="edit"><FONT SIZE=-1><EM>Edited by jc14all on 06/04/02 07:27 PM.</EM></FONT></P>
Anonymous
a b G Storage
June 5, 2002 1:00:52 AM

Good links jc14all,

Exactly the ones I was thinking of.

I have a 29160 card (backwards compatible to 32bit/33mhz PCI bus), I am well aware of the 32/33 pci bus limitations particularly when I run a HardriveTach test, it shows a sustained transfer not that much better than my IDE 7200rpm drive does in the same test.
Although this looks disappointing, I am very pleased with disk-to-disk transfer speeds over the cards own bus.

One day when mainboard manufactures produce a <b>user</b> friendly mainboard with the usual features with 1 or 2 - 64/66 pci slots (there may already be one?) that's not a dual processor board, I will be able to use my SCSI set-up to its full potential, until then I have to put up with about half the bandwidth.

Be wise in your investment choices with SCSI! :wink:
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June 5, 2002 1:18:06 AM

I'm addicted to SCSI even though I only have the Ultra 2940UW2 (80 mb/sec), I am satisfied. I have dreams of having a Ultra 320/640 SCSI setup one day, but my money isn't long enough.

<font color=purple><b>An average human brain weights aprox. 3lbs., but a thought weights a load.</font color=purple></b>
Anonymous
a b G Storage
June 5, 2002 1:23:41 AM

Yeah I know what you mean, I am stuck with it because I have invested heavily in it or I love it depending on how I feel, but I am not diaapointed.

<A HREF="http://www.koalanet.com/australian-slang.html" target="_new">Aussie slang</A>
June 5, 2002 5:16:22 AM

would you like a three channel U2W RAID card with 64MB cache?

What's the frequency, Kenneth?
June 5, 2002 6:53:01 PM

I'm liquidating, everything must go!

What's the frequency, Kenneth?
June 6, 2002 3:02:33 AM

I have a 64 bit RAID card and it does very well in sustained transfer, the burst is limited by the PCI bus. I WISH AND PREY FOR A BOARD WITH 64BIT PCI!!!! I wont pay $400 for a dualie board with 64bit that I wont use, although I have been very tempted.

Jesus saves, but Mario scores!!!
June 6, 2002 3:04:41 AM

HMMM actually I just looked and the Tyan dualie boards are now under 200$....drool drool (even though I just want the slot not the duals =)

Anyone know how well AMD760 works in single CPU compared to VIA's KT266a or single CPU on AMD760? Is there any diff in the Chipset at all between single and dual AMD760?

Jesus saves, but Mario scores!!!
June 6, 2002 11:34:59 PM

Actually, your not going to notice much of a difference going from 32 bit to 64 bit unless you are on the threshold of the 32 bit pci slots limits which typically occurs at or around 100-110 MB/s ( that is of course unless you have a VIA chipset but that is an entirely differnt matter ). Most 64 bit cards are backwards compatable and will work fine in newer motherboards, providing the motherboards layout itself allows for the insertion of a full size card. Bear in mind I am not saying the performance will be exactly the same but it will be negliable.

It's not what they tell you, its what they don't tell you!
June 7, 2002 2:11:48 AM

I really can't answer your question, but I thought this was a nice site with a database of 620 different M/B's to browse. <A HREF="http://www.acme.com/build_a_pc/boardfinder/" target="_new">ACME</A> I sure wouldn't mind getting a M/B with a 64 bit AGP & pci slot. One for a decent 64 bit graphic card and one for my Ultra 320/640 SCSI controller, three DDR333 slots...<pinch><pinch> I'm dreaming :frown:

The Asus A7V333 comes close <A HREF="http://usa.asus.com/mb/socketa/a7v333/overview.htm#" target="_new">ASUS</A> but no cigar!

<font color=purple><b>An average human brain weights aprox. 3lbs., but a thought weights a load.</font color=purple></b><P ID="edit"><FONT SIZE=-1><EM>Edited by jc14all on 06/06/02 09:18 PM.</EM></FONT></P>
June 7, 2002 2:21:38 AM

5 10000RPM LVD160 drives running in RAID 0 =) I can sustain transfers that my PCI is the bottleneck for!

Jesus saves, but Mario scores!!!
June 7, 2002 3:43:57 AM

HAHA nice! SIMMS!! I had a drive controller (not RAID) that had 4 30 pin slots for cache on my 486!

I have a ServeRAID 4H mainly cuz I bought a dead server from a local company that was goin outta biz and it came in there. $200 for a full server and the CPU was blown, which I knew ahead of time. Got a bunch of SCSI drives and the 4H as well as a gig of ram, a real nice tower, and some other goodies, well worth it.

http://www.pc.ibm.com/qtechinfo/MIGR-4JGUDU.html?lang=e...

Jesus saves, but Mario scores!!!
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