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View Full Version : offtopic: Know of any true double PCIe16x boards?



michagl
02-19-2008, 11:53 AM
I realize this question is completely inappropriate for the forum, but I figured someone onboard would have a smartass answer for me.

Basically my PCIe16x slot just burned out on me. I bought a new card on the chance it would be the card knowing I needed a new one anyhow. So I presumably have two PCIe cards now. The machine still seems to work with a vanilla PCI card, so I would like to build a new machine with two true PCIe16x slots that can drive two cards independently (non-SLI) on four displays (two each per the cards)

This wasn't possible when I built the failing machine a few years ago, but I'm getting mixxed messages googling around that it might be now days.

So if anyone would like to set me straight in one way or the other, please do :)


PS: Feel free to move this thread to general discussion or wherever, but please give me a few days to draw some attention first :)


editted: Looks like Via was planning something like this with a technology dubbed DualGFX. It seems to have went the way of the dinosaurs, but that could've been because it became obsolete. In any case I'd like to know for one.

michagl
02-21-2008, 05:01 AM
Come on, no definitive answer?

knackered
02-21-2008, 09:07 AM
apparently not.

michagl
02-22-2008, 06:54 AM
I've been browsing online board manual's. A lot of boards claim to have 16/8x secondary slots. It isn't quite clear whether this means it looks like 16x / fits a 16x based card, but really runs at 8x in SLI/Crossfire modes, or if the slot can actually be used as an 8x slot when not in SLI/Crossfire modes.

My previous SLI boards secondary slot claimed to be a 1x slot when not in SLI mode. And indeed I tried yesterday to put the 16x card into the secondary slot just incase the lanes were rerouted somehow when the primary slot is empty. The slot did work for normal video, but blanked out in a hardware accelerated environment.

So the possibilities seem bleak, though I don't understand why the industry is not pursuing the ability to support multip PCIe cards running independently other than the controllers seem to have a fixed number of lanes to work with. Stacking PCI cards is not a problem afaik.

The operative question at this point seems to be whether 16x slotted cards are able to function in an 8x mode. If that is not possible then there would be no more room for speculation.

Also I'm curious whether these Crossfire boards will work just as well with Nvidia cards as long as SLI is not desired? I assume that is a no brainer, but just to be safe.




PS: If anyone is curious, you might try moving your PCIe card to your secondary (or take out the primary if using SLI) and see what happens. Again, I was able to get non-accelerated video on my machine that way. I'd be curious to know if anyone can get accelerated video on the second slot (and what model boards they're working on if so)

Zengar
02-22-2008, 10:19 AM
Ask at beyond3d forums, they'll know stuff like that

elFarto
02-22-2008, 02:31 PM
PCI Express cards will negotiate to find the highest speed possible. I saw a few tests when PCIe first came out where they covered some of the lanes on the card with tape, and it worked perfectly well (albeit at a slower speed).

A quick search shows Asus' M3A32-MVP Deluxe having 4 x16 slots, 2 of which can be run at x16 at once (if you want to use all 4 at once you need to lower them to x8 each).

You don't say which platform you are using/wish to use (Intel/AMD, NVIDIA/ATI), which make it a bit difficult to find a good board for you.

Using 2 graphic cards in one machine should work perfectly. The most you might have to do is force Crossfire or SLI off.

Regards
elFarto

michagl
02-22-2008, 08:22 PM
PCI Express cards will negotiate to find the highest speed possible. I saw a few tests when PCIe first came out where they covered some of the lanes on the card with tape, and it worked perfectly well (albeit at a slower speed).

A quick search shows Asus' M3A32-MVP Deluxe having 4 x16 slots, 2 of which can be run at x16 at once (if you want to use all 4 at once you need to lower them to x8 each).

You don't say which platform you are using/wish to use (Intel/AMD, NVIDIA/ATI), which make it a bit difficult to find a good board for you.

Using 2 graphic cards in one machine should work perfectly. The most you might have to do is force Crossfire or SLI off.

Regards
elFarto

Thank ye sir Farto :)

Since you asked I guess I've two Nvidia cards and a lot of PC3200 ram laying around. I usually go with AMD on graphics rigs.

Otherwise I was just curious were it possible at'all.


PS: A board under 200$ would be a blessing ;)

If you think just about any contemporary board would do the trick I'm sure I'll have no trouble ferreting something out. On the other hand it appears only that board is marketing itself as supporting multiple displays (being called "Multi-VGA Support") ...If that is the case I might have to go with it. If anyone has the goodies/curiosity on hand to try such a scenario on other boards I'd be very interested in the results. Otherwisee I'm a little skeptical still I'm afraid :p

Oh and, what was your "quick search" query again?!

elFarto
02-23-2008, 03:05 AM
The quick search was "dual pciex16" :)

After a searching a bit more, I came across the Asus M2N32-SLI which is $179.99 from Newegg (http://www.newegg.com/Product/Product.aspx?Item=N82E16813131011). Unfortunally it's only an AM2, not AM2+ board as NVIDIA does not have an AM2+ chipset out yet.

There's an Asus A8N32-SLI, which is a socket 939, takes DDR and has dual PCIe x16 slots. Not too sure on price, but it is an older board, so it shouldn't be as expensive as the one above.

Regards
elFarto

michagl
02-23-2008, 07:43 AM
The board I'm replacing is an A8N-SLI... I'm not sure if that is different from the 32 variety, but 939 seems to be old hat now days.

To be honest though, I'm extremely skeptical these boards would support two PCIe cards not in SLI-mode. The wording of the M3A32-MVP pitch is clear that it should, but it is the only board I believe on the market making this claim, while the language surrounding other boards are nebulous at best. If that was a standard feature, then there would be no need for suuch a premium board to parot itself that way.

I basically have two options the way I see it. Either buy the M3A32-MVP and all the other custom parts it will surely require, or pickout a generic board that will work w ith the spare parts I have and run the risk of it not working out -- at which point I'll have to spend at least the board difference on a new PCI card, which will have a limited graphics feature set and trash/put-away the spare card.

I'm accustomed to the secondary being a PCI card, so financially I'm just left to balance out the cost of custom ram/power versus investing in a beefier machine with wider options.

I'd really like to hear a personal account of someone running two+ PCIe cards on a generic SLI/Crossfire board. I have been unable to come accross a single mention of success in such a setup on the internet.

elFarto
02-23-2008, 09:13 AM
The A8N32-SLI has an extra chip the A8N-SLI doesn't. This gives it 16 more PCIe lanes.

Here (http://forums.nvidia.com/index.php?showtopic=46814) is a thread where someone states he has used 2 6600GTs on an A8N32-SLI to run 3 separate screens.

I would be very surprised if you couldn't use the graphics card separately.

The A8N32-SLI is probably the cheapest route, a quick look on ebay and it's about $100.

Regards
elFarto

michagl
02-23-2008, 09:05 PM
I suppose I might as well just try to swap out my board with the A8N32-SLI then, see how that works out :)

I appreciate the patience/assistance senor~ Farto!

sincerely,

michael

editted: Just for the record, that thread hung on the point that the board worked before with two identical cards in non-sli mode, but after trying two different cards it apparently killed the board :p

michagl
03-16-2008, 08:39 PM
Just for the record, I did purchase a board on Ebay from a Canadian operation. Ran normally for a few minutes, then died beautifully -- returned.

Faced with the prospect of building a machine from virtually scratch, I recently ran into some money, so I decided to just invest in a higher end laptop in the hope it'll still be running the day it is tossed, so I shouldn't be without a work ready machine this long ever again.