ddrueding

Pci Bus Traffic Concerns

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The Tomcat K8S...at first glimpse exactly what I'm after.

Dual Gig-E, 4-channel SATA RAID, and onboard graphics.....great! :D

But wait....is that a 32-bit/33-mhz PCI bus I see? :blink:

No, this must be some kind of mistake...open up the PDF featuing the block diagram. Despite not being able to read the text, after staring at it long enough, I'm fairly convinced that is what they did. :unsure:

So here's the question...why on earth would you bother with the cost of all these goodies if you're going to limit it to ~80Mb/s? And with both the drives and the NIC on the same bus, that's ~40Mb/s? WTF? FTS.

Or am I misunderstanding the situation.

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the board has 6 PCI slots... with onbaord PCI graphics.... 2 non integrated ethernet controllers and an Si S-ATA controller?

that's odd... i could swear that maximum number of PCI slots per PCI bus was 6.... maybe they are using multiple PCI busses?

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maybe they are using multiple PCI busses?

The block diargram doesn't show anything like that :unsure:

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yeah, I agree the block diagram indicates a single 32/33 PCI bus full of crap. Obviously not the design that an enlightened person would choose for a well balanced machine.

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I thought that 32/33 PCI was limited to the speed of the FSB? i.e. 133 MHz FSB = 133 MB/s. 166 MHz = 166 MB/s. Unless I'm mistaken, but I remember overclocking my system before. (Well..I guess that's SORTA right considering that PCIs have a 4:1 FSB-to-PCI clock speed divider.

I think that this is a case where they tried to either put too much to sell the product or didn't think through it.

Also figures that it's probably designed more for DB or webserving than anything else. *shrug*. I have no idea.

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PCI bus speed should always be 33Mhz (in it's standard implementation).

In the "olden" days (read: a year or so ago), this was accomplished by changing the multiplier on the PCI bus as a ratio of FSB to maintain 33Mhz. If you overclocked such a motherboard, you were likely changing the PCI bus to something out of spec, this could cause data corruption, instability, etc.

More modern (read: current) boards are able to lock the PCI, AGP, and memory speeds independantly of the FSB.

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Tyan should never have put dual GigE or a SATA RAID controller on this 32/33 PCI bus.

Then again, they had their hands tied since:

- Tomcats MB are their budget line

- they so far appear to want to stick to AMD chipsets (nothing wrong with that)

- the AMD-8111 'IO hub' has no support for GigE, SATA, or 64 bit PCI (only 100/IDE/32bit 33MHz PCI respectively)

- the Tiger Opteron boards add the AMD-8151 'Graphics Tunnel' but still have the same limitations as that Tomcat

- only the Thunder Opteron boards get the AMD-8131 'PCI-X Tunnel', which allows a proper implementation of all the goodies. Something tells me this 8131 chip isn't exactly cheap...

While I reckon a Thunder K8W would be my dream board, for a single CPU solution a more modern 3rd-party chipset may be a better solution than one based on just the AMD-8111, as opposed to the full 3-piece AMD chipset.

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I think this would make a great little app server.

The EIDE ports should be attached directly to the I/O Hub (according to AMD's documentation), whereas the SATA would connect to the PCI bus. I agree that this setup is ironic.

So, if you use PATA and the GibE this little guy would cruise.

With SATA, you would get 60MB/sec with your GibE and 50MB/s with your drive.

Still not bad.

I kinda like this little guy. Put a x48 in it, load it with 4GB of RAM and you've got a powerful app server - i.e. cheap blade-concept system

The six PCI slots baffle me, but other than that it fits a popular niche in the market.

Cool.

Dogeared

8^)

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TYAN IS FULL OF SIHT!

Tyan advertises one thing, and REFUSES TO SUPPORT ANYTHING BEYOND COMPLIANCE.

I had a 430TX Mobo that was SUPPOSED to do 83MHz FSB (Socket 7 days).

When set to 83, it actually ran at 55MHz.

I called Tyan and told them to replace my defective motherboard.

They said they only support 50MHz, 60Mhz and 66MHz speeds (the official speeds at the time)

A week later the Primary IDE channel died. I was happy, maybe the next would work.

They replaced it with another broken one, the DIMM slot didn't work, and 83MHz was still actually 55MHz.

That was only ONE Tyan board. I also had a Tomcat III which didn't work too well eith and Bank0 (RAM) never worked.

Tyan is garbage. If its features look too good to be true, IT REALLY IS.

They can write whatever they want, and only support what they have to.

They are CROOKS.

Tyan should get bombed by terrorists for being dirty bastards.

Heru'wer

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I wouldn't go so far as to call Tyan a bunch of crooks, but I have been left a little miffed with their design choices. I mentioned this in another thread, but to recap, I have a Tyan Transport GX28 1U server case with built-in s2880 Tyan thunder k8s m/b. I assumed from the start that the on-board SCSI would be easy to upgrade to RAID using ZCR. Well, lo and behold, the ZCR slot is inaccessible in this server. So, I decided to buy an LSI 320-1 RAID card (I wish they had 1X versions), and on trying to fit this card in the server, what do I find?... A tall capacitor makes it impossible to fit (ultimately i had to strip the card of its backplane and fit it in another slot --messy). Ultimately, this was not the right m/b for this 1u server.

On the positive side, their server case is very well built. The hot swap drives, the SCA backplane, the cooling/air flow design, all top-notch. There aren't that many 1U cases that support 4x hot-swap scsi, with dvd-rom and floppy. The only thing missing is a scsi connector at the back for external devices.

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On the positive side, their server case is very well built.  The hot swap drives, the SCA backplane, the cooling/air flow design, all top-notch. There aren't that many 1U cases that support 4x hot-swap scsi, with dvd-rom and floppy.  The only thing missing is a scsi connector at the back for external devices.

My current favorite 1U rack case for many purposes. Note the trays can be ordered for SCA or SATA. I briefly considered Transport solutions, but building based on this case I think is better. This is server-room gear; if you are worried about a bit of noise look elsewhere.

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So now I'm considering an Intel chipset from supermicro, the P4SPA+.

It seems to have it's dual-channel SATA RAID off the PCI guss and the Gig-E on the 66Mhz PCI bus...looks better.

1. Are there any with a 4-channel SATA RAID or Gig-E off the PCI bus?

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I think the GigE is on PCI-X bus A @ 100MHz. And the SATA is connected to the 8111 via the bog standard 32-bit PCI bus @ 33MHz. If I'm not mistaken, you can only have 1 PCI-X device on the bus if you run at 133MHz... As soon as you add two devices to the bus, you will have to drop down to 100 or 66MHz.

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I had a 430TX Mobo that was SUPPOSED to do 83MHz FSB (Socket 7 days).

When set to 83, it actually ran at 55MHz.

That was a fault with the PLL that had the spread spectrum modulation going to the same bit as the frequency selection. In other words, you would get two different frequencies depending on whether you had that option enabled or not. Took them awhile to figure that one out.

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I think the GigE is on PCI-X bus A @ 100MHz.  And the SATA is connected to the 8111 via the bog standard 32-bit PCI bus @ 33MHz.  If I'm not mistaken, you can only have 1 PCI-X device on the bus if you run at 133MHz... As soon as you add two devices to the bus, you will have to drop down to 100 or 66MHz.

Yep, my bad....I think it'll still work for my application. And is a far cry better than the motherboard I mentioned earlier.

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I think the GigE is on PCI-X bus A @ 100MHz. And the SATA is connected to the 8111 via the bog standard 32-bit PCI bus @ 33MHz. If I'm not mistaken, you can only have 1 PCI-X device on the bus if you run at 133MHz... As soon as you add two devices to the bus, you will have to drop down to 100 or 66MHz.

PCI-X spec is one device 133MHz, two @100MHz, more @ 66MHz, I believe.

That's 533, 400, and 266 MB/s theoretical, btw.

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That's 533, 400, and 266 MB/s theoretical, btw.

Double all three of those numbers, but yeah.

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So I end up with a RAID 10 array of 740GDs limited to ~70MB/s due to the 32/33, but without any competition on that bus.

I get a Gig-E controller on it's own PCI bus "limited" to 500MB/s on the 64/100 PCI-X

And I have another PCI-X 64/133 bus to play with as I please...right on!

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I can't say I've had experience with Tyan's lower end boards, but their Thunders have been rock solid for me.

We're running 40+ boxes with dual Oppies with Tyan Thunders no problems to this day. Just don't have dual Athlon MPs in 1U boxes.

I have warrenty from another company, not Tyan so I dunno what Tyan's warrenty is like.

Heruwer, sorry you had a bad time with Tyan, but I have friends that say the same for Asus, Gigabyte, and Supermicro ( :huh: yeah I know).

Ddrueding, that a REALLY SWEEEEEEEET mobo. The diagram has 1 mistake. The RAM should be 266/333/400. The 246/248s have a 400Mhz RAM controller.

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The diagram has 1 mistake. The RAM should be 266/333/400. The 246/248s have a 400Mhz RAM controller.

Yeah, I got that part...the RAM I selected is PC3200 anyway (in case of later upgrade)

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Tyan can get extremely snippy about RMA returns. They act like you just ran over their favorite pet in your four-wheeler.

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