Old Standard PCI 32 Bit Slots - 133MB/Sec Max... Question 1

[kjv1611]

Old Standard PCI 32 Bit Slots - 133MB/Sec Max... Question

I don't remember for sure seeing any documentation showing exactly how the 133 MB/sec limit works. Is that "per slot" or for the whole PCI bus?

So if it's for the whole bus, and you have 3 or 4 PCI cards, then they are limited to a total of 133MB/sec between the attached devices, or are they limited per slot?

I'm Googling around as well on this.

Thanks for any thoughts.

 

[kjv1611]

I think it's a total bus limit, but I'm just wanting to get some other inputs to be sure I'm reading it right.

And considering it's the whole bus limit, I may just not even consider what I was thinking about doing.

Basically, I have a machine that was given to me that I was considering turning into a "publishing system" in this way:

1 SSD for the system, using a PCI SATA 150 card that I already have - don't have the SSD yet..

2 2TB hard drives on another PCI SATA card..

2 SATA DVD Burners

2 IDE DVD Burners

The burners would all be run off the system, b/c they won't run off the SATA RAID cards I've got. Though if they could, I'm sure I'd be better off using the SSD and one of the hard drives... or either the 2 hard drives.. on the onboard 2 SATA ports of the old motherboard.

But I don't know. I may just scrap that idea all together for now. I'll probably be better off just using external or docked hard drives for backups, and getting a DVD duplicator, I suppose.

Just a lot of thoughts going on my brain right now, which I really don't have time for.

 

[BadBigBen]

peak transfer rate of 133 MB/s (133 megabytes per second) for 32-bit bus width (33.33 MHz × 32 bits ÷ 8 bits/byte = 133 MB/s)

source: Wikipedia

what it boils down to is that the limit of 133MB/s is for the whole bus, and for each device, since only one device at a time can have access to the bus for Data transfer (4 bytes every 30 ns or so, then the next device or that device again, depending on the BUS ARBITER)...

(at least that is the way I understood the PCI papers, wikis, etc. I read and it's been a while)



Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"

 

[cdogg]

Yes, 133MB/s is the total limit for all devices going through PCI. And like Ben pointed out, each device has to take turns using the bus which explains the use of IRQ assignments. So generally speaking the more devices you have sharing the bus, the more congestion you'll have effectively slowing each one down.

Do you already own the PCI SATA cards? If not, you'd be better off using that money towards a newer system that has SATA integrated on the motherboard.

~cdogg
"All generalizations are false, including this one." - Mark Twain
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[goombawaho]

Maybe you can take a crack at my (still unanswered and somewhat related) question.

http://www.tek-tips.com/viewthread.cfm?qid=1626982&page=1

This is what we call a covert bump.

 

[kjv1611]

cdogg, I do already own the PCI SATA cards. Otherwise, yes, I'd defintely think it not worth buying new PCI cards.

I foolishly bought a heap of these cards way back when the went "on sale" - really what was going on, was the mfg quit making them, and the stores needed to unload.

Then again, when I first got them, they GREATLY improved what I was doing at the time. They've been really good cards to date.

And I figured that with the system I was thinking of setting up (already have the system, but just changing some things), it might be good enough for what I was wanting to do.

Here's what I have right now:
[ul][li]Case = Chieftec full tower with plenty of bays - 4 external, and several internal, I think(If I remember correct)[/li]
[li]Installed PSU = 300 Watt, and I think a no-name one at that/cheapie brand. If I do this, I plan on putting in a new PSU with plenty of SATA connections, such as one CoolerMaster I saw on sale at NewEgg for $60 or $70 - 600Watts - though that might be overkill[/li]
[li]Mobo = MSI Neo 2 - P Platinum[/li]
[li]Current CPU = Celeron (p4 line)[/li]
[li]RAM - Not sure what's installed, but I think I'll be able to bump it at least to 1GB or 2GB, DDR[/li]
[li]Hard Drives - What it has is what I plan on replacing. Current is a couple IDE 150GB drives.[/li]
[li]My thought is to use an SSD for system (on one PCI card, and 2 or more large hard drives on another SATA card - it's a RAID card, so I can setup either a RAID 1 or RAID 3, depending upon number of drives. All the drives would need to be purchased... currently thinking 2 2TB hard drives for a RAID 1 setup[/li]
[li]Optical Drives - Planning on putting in 4 new DVDRW, it's not like those are expensive now anyway. 2 IDE, 2 SATA[/li]
[li]Graphics - won't really matter, but I think it does have an AGP card installed as it is.[/li][/ul]

So with buying the new drives, I would end up spending:
[ul][li]$60 or $70 on new PSU[/li]
[li]$60 to $80 on new DVDRW drives[/li]
[li]$115 on SSD[/li]
[li]$200 on 2 hard drives[/li][/ul]
So, total = $435 to $465

That's why I started backing down from the idea. Of course, I can cut a fair amount out of the cost by not going SSD. But if I do set this up, I think 2TB will be a necessity of the storage, and figure RAID 1 would be good for the particular use.

My thought with it is to have a system that will be a backup of all the data files (audio and video primarily), and then it'll be a publishing system besides that, allowing to burn to 4 disks at the same time.

I've actually kept my home "main" system like this for about 5 or maybe 6 years, now. For some of the things I do, it works out really well.

We have the money in the budget to pay for the parts, but I'm just going to sit on it, think and wait. Of course, I already own the system, and if I get the time in the next couple months, I can just try using some drives I have at the house, and see how it does. We'll see about that - too many various projects as it is.

 

[cdogg]

Just so I'm on the same page, you are looking to replace the IDE hard drives with IDE burners and add 5 SATA devices (1 SSD, 2 HDD, and 2 SATA burners)? That's a pretty big load on the PCI interface. If you could lose the 2 SATA burners, it might not be that bad. Then again, it's probably going to be one of those trial-and-error deals.

Keep us posted on how it turns out!

~cdogg
"All generalizations are false, including this one." - Mark Twain
[tab][navy]For posting policies, click [/navy]here.

 

[kjv1611]

Yes, that's right... but.. I ddidn't specify for the burners...

ALL the burners will be connecting to the onboard connections - none on the PCI bus. One on each IDE connection, one on each SATA connection.

The SSD will be on one PCI card, and the 2 hard drives will be on another PCI card.

 

[cdogg]

OK, I must have missed something. The motherboard already has two integrated SATA ports then, which you are using for the SATA burners?

If that's the case, then it's worth trying to see how it turns out. If it doesn't operate well, you can always reuse the SATA devices in another system. My only remaining concern is the SSD drive. Those beasts are able to transfer well over 133MB/s, especially if you go with one of the newer ones from Intel. The SSD would be able to saturate the PCI bus all by itself.

~cdogg
"All generalizations are false, including this one." - Mark Twain
[tab][navy]For posting policies, click [/navy]here.

 

[kjv1611]

Yeah, that's what I was thinking about, too. I thought it'd be "nice" with the performance, but if it ended up basically blocking out everything else, then it'd be defeating the purpose.

Basically, I'm trying to use some old hardware to make do with. However, I'm sure I can just keep my eyes out for a newer mobo with more SATA ports onboard, which is what I'd rather deal with anyway, honestly.

But, who knows. I'll just play with it and see. I might use one of the SSDs we already have (or will have in a few days) just to see. Worst case scenario, I'd just format it if it doesn't work out, I suppose. I could still use the large case, and just stick the older mobo/cpu in an older case with it's current PSU, and use it for some other test/toy/give away, I guess.

And then, I'm sure I have another SATA drive around which I could use for the system drive otherwise..

I could definitely reuse the drives, and I did almost go ahead and get them, but I figured I'd wait for now, b/c I've got some other issues that are more urgent. Besides, if I wait longer, prices would likely drop more, as typical.

Thanks for the thoughts.

 

[BadBigBen]

aren't all the internal connectors (SATA/IDE) also on the PCI BUS, and definitely any onboard graphics controller, afaik...



Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"

 

[cdogg]

Ben,
Not necessarily. It depends on the chipset. Early versions of the SATA ports did go through PCI, but not too long after SATA was released, chipsets were modified to give SATA a direct link to the "southbridge" bypassing the PCI interface altogether.

It's been a while, but that's what I'm recalling from memory anyway. I'm sure someone will have the time to look that one up!


kjv1611,
Assuming that the SATA ports on your mobo have a direct link to the southbridge, it might do you good to put the SSD on one of those ports and one of the other hard drives on the other. Then put both both SATA burners on one PCI card, and the last hard drive on the other PCI card.

Just a thought...

~cdogg
"All generalizations are false, including this one." - Mark Twain
[tab][navy]For posting policies, click [/navy]here.

 

[Triton101]

also, in my opinion, the big advantage with SSD is that it's the random reads/writes (aside from random access) that make the system more snappy and usually those are well below the maxes of the buses.... (but they are getting better/faster with newer SSD drive controllers)

__________________________________________________________
Find a job you love and you'll never work a day in your life. - Confucius

 

[kjv1611]

Well, I didn't think about everything possibly being on the PCI bus. I have no idea about this one. I might try looking it up some time to see.

I did do some tinkering and testing around with parts I had around the house.

Right now, this is what I've got (put together early last week):
P4 CPU, 2.8GHz - 478pin.. swapped it out from another system that had a bad mobo, so was just sitting there. took out the celeron. Figured if I got it running, the P4 over the Celeron would give a little bit of help.

Tried various bits of RAM. Anything from 256 or 512MB up to 2GB total, diff speeds as well... DDR-266 to DDR-400.

I did get the system "running" with 3 hard drives (1 separate on an onboard SATA, 2 others on a PCI SATA RAID card, which defaulted them to a RAID 0 - I could care less for now, for testing.

Also I have 2 SATA and 2 IDE burners installed - 1 on a PCI SATA adapter, and 1 on the other onboard SATA connector. Each of the IDE burners is using it's separate channel (I've been down the road before of using 2 drives on one IDE connector, when burning to multiple drives, and I DO NOT recommend it).

The machine also has a VGA graphics card - nothing much of anything, performance-wise, but not bottom of the barrel, I forget the model. Anyway, I happened to notice that the fan wasn't running on it, so I made do with a CPU HSF I had sitting around. It aint pretty, and it aint by the book, but I figured I don't have anything to lose at this point, and this way I can say I've done it.

And I installed an extra 120mm fan (I think that's the size) in the rear of the case, as there were no case fans installed previously.

The PSU is a 300 or 350 Watt "no name" PSU. Well, it has a name, but I believe it's one of those lower end, generic, brands, from what I've seen.

So, I ran various tests. Ran a couple different memory tests, at least one hard drive test, that sort of thing. All worked fine. And at one point, I was able to boot to a CD version of WinXP. But at the current settings or hardware connected, I've not been able to boot to that same copy of XP. It just hangs at that. This is all for testing.

I did also attempt to install one Windows copy to the hard drive, but same thing there - would hang after a while.

I think I'll try disconnecting all but one of the burners for now, b/c a couple seem to be acting funny.... and I'm wondering if the PSU just isn't up to the task as well.

In the end, I may just skip using an SSD in this one anyway... I don't know. I think I can get it going enough with or without it. Also, I got to thinking - I could spend a little more, and get one with more space, put that in our main system at church, then pull the current system drive from there (velociraptor), and maybe put it in this extra system.

Right now, I'm still just playing around. Didn't have much time last week to finish it out, and this week, I won't have time until the weekend, at earliest, so not sure what I'll do.

Now besides all of this, I also have a couple other boards/CPUs and such laying around... maybe I should look at one of those instead. I don't remmber what they all are, but I know I at least have:
1. AMD Athlon 3200XP + (was mine originally.. ended up coming back to me after the last person got a new PC) - running on a Gigabyte GN7NN or whatever the model # was - pretty loaded board at the time.

2. AMD athlon XP or maybe an Athlon 64... not sure, I just don't remember. Was given to me, and I've not touched it yet. Sadly, no time, so it's sat in a corner for too long.

3. Others that wouldn't compare to the P4 or Athlon XP..

It's amazing what you end up with when people find out you know anything about 'puters. It's like, "hey, I was going to throw this away, but figured you might want it." A few times, more later than earlier, I've said many times, "thanks, but no thanks - too much digi-junk as it is".

I just looked up my motherboard, and according to anandtech (old review), the SATA ports on that board ARE bound by the PCI bus:

http://www.anandtech.com/show/1119/2

So, I'm thinking I would NOT want to use the Gigabyte board for this setup for sure. Sad.

Besides all of that, I've got to sort through all my mess of parts, wires, and such, soon, and during that sorting out, I'll try and swim back towards the one I'm not sure of... I think it's an Athlon XP or else Athlon64. We shall see. If that board is better, I may just use it instead for this project, and think up some other use for the other. Surely I can do something with it.

 

[cdogg]

==> I just looked up my motherboard, and according to anandtech (old review), the SATA ports on that board ARE bound by the PCI bus

Yes, that's unfortunate. When I went digging through Google, I found several links that implied that an integrated SATA host controller didn't appear on an Nvidia chipset until the Nforce4 chipset came out in 2004. Intel had one out in 2003 on the ICH6. But just about everything before that for SATA in either product line is going to be bound by the PCI bus.

~cdogg
"All generalizations are false, including this one." - Mark Twain
[tab][navy]For posting policies, click [/navy]here.

 

[kjv1611]

Well, yeah, that kinda stinks. I just looked up the current project board - the MSI board - here:

http://www.msi.com/index.php?func=proddesc&maincat_no=1&prod_no=150

And it's ICH5 which would put it in the "pre" period, where it'd too be limited by the PCI bus.

Well, I guess I'll look at the other board yet to see what it is. I imagine I could still get by with it, since I had used the same Gigabyte GN... AthlonXP board with a similar configuration in the past... it worked, but no where near as well as the newer Core 2 Duo system I built later on.

And if that one is also PCI bus limited, I may just wait and see what I can find on eBay. I don't want to dump much money into that particular aspect. Or I can simply play a waiting game.

Well, then again, as was mentioned, the SSD benefits are also dealing in areas that wouldn't be as limited, if at all, by the bus speed. And total devices would be (current idea, anyway):
1. One SSD or fast HDD for system
2. Two SATA hard drives in RAID 1
3. 4 DVD Burners (2 IDE, 2 SATA)

Whereas initially, with the Gigabyte Athlon XP board, I had:
2 Raptors in RAID 0 on one PCI RAID card
5 WD 500GB drives in a RAID 3 config on another PCI RAID card
4 DVD burners - I forget the final configuration, whether I did all IDE, or whether I did a couple SATA...

And at the time (before I got the Core 2 Duo), that system seemed to do okay - gaming, audio editing, cd/dvd burning, etc..

Hmm... only will know with testing... but may just not take the time... surely I can find someone wanting to part with an older yet newer-than-these systems (if the other spare isn't up to par) that will do. We shall see.

Thanks for all the thoughts and suggestions, but particularly to BadBigBen for mentioning the PCI bus limitation possibly including ALL attached drives, basically.

 

[kjv1611]

As yet another update. Last night, I was working on another computer using the same KVM switch I had this machine hooked up to anyway, and was mainly in that room trying to do some clean-up in the room. So, I figured I could work on this at the same time.

I went ahead and unplugged (power) from every "drive" except 1 DVD drive and 1 hard drive. After doing this, it seemed to work really well. I ended up installing WinXP on it, and no errors or major hiccups. It did give some issues with a Win7 installer, but the disk may have been damanged there, not sure what the case was.... and at the time, I had not disconnected the other 2 hard drives.

And I did some thinking - even if the total speed is limited byt he PCI bus, in this case, the primary use of the machine will be in burning CDs and DVDs. So, only so much data will be used at the same time anyway. So maybe I'll go ahead with it after all. Right now, the system seems pretty peppy. I am running it on one 74GB Raptor and one DVD drive. I guess I could just let the old raptor go, personally, and leave it in there for starters and that way only need 2 data drives and a PSU.

Well, too much to think about, and not enough time.

Gotta go.