mainboard advice needed

[Dogbert]

Check the dates on these reviews. They're from before April 2002.
They're all abou the 1st model and not the 4m model.

[VJ]

So you're saying the 4m model is the model with the USB bug fixed ? And thus that the S2466N didn't have USB because of this bug ? Well, I did some searching, and found this review of the s2466n-4m. It makes no mention of any USB problems, and is dated April 26th. http://www.tweakers.com.au/articles/...466n/page1.asp

So this backs up your statement. Guess this Tyan still is a very good candidate (minor point according to this last review was the bios, but this has probabely been revised since then).

Thanks !


Jörg

[Ribbit]

Here's the deal with the 2466:

The original version of the MPX chipset had a bug in the USB. It was actually quite minor, but Tyan saw fit to take the USB off the board and give you an extra card. The chipset has now been fixed, and all current 2466 boards have onboard USB (and no extra card).

All 2466s being made now are 2466N-4M models, and all 2466N-4M models have onboard (and working) USB. They also have a good onboard NIC (3c905) to save you another PCI slot.

If you're really looking to save slots and have money to spend, look at the 2468 (Thunder K7X) which adds onboard PCI video (you still get an AGP Pro slot), a second NIC, and onboard dual-channel U160 Adaptec SCSI, at the cost of I think 1 slot (so you get 5 PCI slots instead of 6). All Thunder K7Xs have onboard USB - they were never released with the buggy chipset.

Hope that clears all that up.

PS - If you're looking at an add-in SCSI card, I'd take a look at LSI.

[VJ]

Ribbit:
Thanks for confirming things.

I have looked at the specs of the Thunder K7X, but I think that puts to much things onboard: I'd like to go Matrox for video , and I don't really need a second network. Onboard SCSI might be convenient, but I tend to prefer seperate controllers (onboards often don't offer bios-updates, and sometimes have some issues in other OS; finally, bringing an onboard SCSI outside the case - which is needed for scanner/zip - can also require some non-standard cables, which are then very hard to find). But I'll check some prices and specs.

I have heard good things about LSI, but SCSI is already quite hard to find here, and then the stores only offer Adaptec. But the 39160 seems to contain what I'm looking for (64 bit PCI, dual channel).

Thanks !


Jörg

[VJ]

Well, the cheapest route would be the K7X:

http://amdmb.pricegrabber.com/search_compare.php//topcat_id=1/page_id=40/topcat_id=1/page_id=40/masterids%255B%255D=564351/masterids%255B%255D=585337/masterids%255B%255D=585338/ut=9dc18c1e5bd5148e/Compare.x=44/Compare.y=9/

If these prices are anything to go by:

Tiger MPX: $206
Adaptec 39160: $399 (from Adaptec website)

Thunder K7X: $455.51 (version with SCSI)

Guess I'll be checking if there are any issues with this onboard SCSI-controller, and what is required to bring 1 channel to the outside of the case.

Is there a way of using the onboard video as secondary adapter (or is it just "primary" or "disabled") ?

Thanks again guys,


Jörg

[VJ]

Just one last question:

Do 32 bit PCI cards work in 64 bit slots ? According to what I have found, it should work, depending on the voltages of the cards (3.3V works, 5V doesn't).
I have read somewhere (but have lost the link) that if 1 32 bit PCI-card is placed in a 64 bit slot, the other 64 bit slot(s) also slow down.

Can anyone confirm this ? (perhaps post a link to information ?)

Thanks,


Jörg

PS: If so, I could still opt for the Tiger 760MPX, filling the 64 bit slots with some of my other cards, thus having the option of going for a cheaper single channel SCSI-controller.

[Ribbit]

I'll take this one then...

PCI comes in two clock speeds - 33MHz and 66MHz, and two widths - 32-bit and 64-bit. You're confusing (or at least blurring) the two.

Assuming the speeds are the same, if you place a 32-bit card in a 64-bit slot, then you've really not lost anything - you're just wasting half a slot. No biggie. OTOH, if you put a 33MHz card in a 66MHz slot, that whole PCI bus will slow down to 33MHz. Not really what you want if you can help it.

Now voltages. 66MHz slots are always 3.3V. 33MHz slots are usually, if not always, 5V. I guess you could make a 3.3V 33MHz slot, but it would be incompatible with half the hardware out there. The key/notch in the slot indicates the voltage, not the speed as most people think. You can look at the notches in the connector on the card to see which voltages it should work at - if there's one near the front, 5V, and one near the back means 3.3V. (Although some manufacturers have both notches in 5V-only cards, so be careful.)

The 64-bit slots on the K7X and MPX (and all the non-Tyan dual-AMD boards) are 66MHz (and therefore 3.3V), so most regular cards won't work in them. (The 64-bit slots on the K7 and MP are 33MHz, all regular cards should work in them.)

I've probably confused you more than I've enlightened you...

[Ribbit]

The onboard video is a PCI device, so it should work in conjunction with an AGP card and/or other PCI cards - it all depends on how well your OS handles them.

As for bringing SCSI out of the case, I'm not entirely sure. I think the way to do it is the following: mount a backplane on the back of the case. Connect the backplane to the SCSI controller and then the internal devices, and turn off the termination on that SCSI channel. If you don't have any external devices, use an external terminator, or you might get away with re-enabling termination on the controller. If anyone has comments on this method, I'd appreciate them.

Of course, you have to watch your cable lengths. And I assume you know about LVD and SE SCSI and why you shouldn't mix them.

Oh yes - why the $^£&! do wide-SCSI cable makers always put the connectors on upside-down? You have to either twist them at every device, mount your devices upside-down, or waste half the cable taking it up the case and back down! If anyone knows where I can get a good kit for making wide cables (SE and LVD), preferably in the UK or Europe, please let me know - it drives me nuts!

And VJ - I got an LSI 21040 dual-channel (one U160, one Ultra-Wide) 64-bit 33MHz controller for about 170EUR (but no cables, software, manuals, etc.), and I've read about others on this board getting LSI-based cards even cheaper. That Adaptec looks awful expensive by comparison...

[VJ]

Thanks for the explanation on the PCI-64 ! (and no, you haven't confused me more , actually, now it is all beginning to clear up). I should check the specs of some of my cards, but I think some of them can be used in PCI64-66 MHz slots...

I did a search on the Adaptec website, and they have a cable that connects to an internal 68-pin and brings this connection to an external 68-pin (in a supplied bracket !). Yes, I am aware of cable length issues, which is why I need 2 channels in the first place (currently 2 LVD-drives + CDRW on 2940UW and on the 2906 a scanner and zip). The orientation of the cables doesn't really bother me: my drives are vertically mounted in a low drive-cage.

That LSI is really a lot cheaper (the Adaptec does van 2 U160 channels, which might account for some of the price-difference). But as I have said before: it is quite hard to find controllers other than Adaptec here .

Thanks for the information !


Jörg

[Ribbit]

Originally posted by VJ
I should check the specs of some of my cards, but I think some of them can be used in PCI64-66 MHz slots...

I should probably clarify - If a PCI slot is 3.3V, it's very likely 66MHz. If a PCI card is 3.3V-capable, that doesn't necessarily mean anything speedwise.

I'd hate for you to go look at your cards and say "hey, that one's 66MHz!", and later find out the hard way that...it isn't...

(And like I said, some makers put both notches in 5V-only cards anyway.)

On the MPX chipset it's very desirable to keep the primary bus at 66MHz because of the way the buses and chipset are logically laid out.

BTW, I'm pretty sure LSI have an online store in Europe.

Glad I could help.

[VJ]

I should probably clarify - If a PCI slot is 3.3V, it's very likely 66MHz. If a PCI card is 3.3V- capable, that doesn't necessarily mean anything speedwise.

Yes that's true, but if I don't have any faster card, it probabely doesn't impact performance if the 66 MHz slots would fall back to 33.

Yes, I'll check for an online store, but I am somewhat reluctant to order hardware online....


Jörg

[VJ]

I justed checked the specs of the Tyan Thunder K7x :

• Two 64-bit 66MHz (one 5/3.3-volt; one 3.3-
volt) PCI 2.2 slots and three 32-bit 33MHz (5-
volt) PCI 2.2 slots

So if one doesn't use 64-bit cards, am I right in stating that one can use 4 "normal" PCI cards on this mainboard ?

Jörg

[Ribbit]

Better ask Tyan to clarify that one. That 5v/3.3v slot concerns me a little. I suspect it drops the bus back to 33MHz if you use/force 5v, but that's not made clear on the site or in the manual.

I'm also interested to know which bus the SCSI controller is on. The MPX chipset only supports 2 devices on the 66MHz bus, and there are two 66MHz slots already, so the Adaptec must be on the other bus (33MHz, 32-bit). Seems silly to put a dual U160 controller on the slower bus.

I'd email Tyan and ask them. Let me know what you find out.

[VJ]

Ribbit:
The mail to Tyan has been sent, I'll post there reply here as soon as I have it.


Jörg

[VJ]

I immediatly got 3 automated replies, one of which shows this link:

http://www.tyan.com/support/html/f_th_k7x.html

On this, there is this question:
-
What is the IRQ routing for my motherboards PCI BUS?

PCI Bus 1 is made up of 2 64bit, 66MHz 3.3v PCI slots.
PCI Bus 2 is made up of 3 32bit, 33MHz 3.3v/5v PCI slots.

The Interrupt routing is:
AGP INTB/INTC
PCI bus 1 slot 1 = INT A B C D
PCI bus 1 slot 2* = INT B C A B
PCI bus 2 slot 1 = INT A B C D
PCI bus 2 slot 2 = INT B C D A
PCI bus 2 slot 3 = INT C D A B

3COM LAN #1 = PCI Bus 2 INTC
3COM LAN #1 = PCI Bus 2 INTD
ATI Rage XL = PCI Bus 2 INTB
Adaptec AIC7899W = PCI Bus 1 INTA/INTB

*On the S2468UGN PCI bus 1 Slot 2 has SCSI Interrupt Steering Logic support. Therefore Interrupt C & D are routed to SCSI Interrupt A & B.
-

This clearly shows the onboard SCSI to be on PCI Bus 1 (the 64 bit/66 MHz). It doesn't answer the question about what happens when the 3.3V/5V slot is set to 5V.
The automated reply stated I should mail the original question to another (supplied) address, if the answer is not on the shown links.

Jörg