so i need a new PC

[wu_trax]

what should i get?
I need a new board, cpu and graphiccard. it doesn't need to be absolutly 'high-end', but it should be ok for the next 2 years.
(and someone please thell me, what the hell is this SLI-stuff?)

[JammyJim]

SLI is the graphics card alternative to dual processors i think.
i.e. you have two cards slotted in and they work together thereby doubling your power. (altho id imagine it would be a little less than double)

[mist]

3dfx 'invented' it way back when, so that you could use multiple voodoo 2/voodoo banshe cards together. you'd put a special cable between teh cards and they'd then render alternate lines of the pictures, resulting in the double speed that mr jj mentioned.

when 3dfx died nvidia bought the tech off them, and have been making noises about it recently. i've not seen a graphics card that supports it from them yet, but i've not been paying attention so there may well be one.

[Structural Integrity]

Originally Posted by mist

3dfx 'invented' it way back when, so that you could use multiple voodoo 2/voodoo banshe cards together. you'd put a special cable between teh cards and they'd then render alternate lines of the pictures, resulting in the double speed that mr jj mentioned.

when 3dfx died nvidia bought the tech off them, and have been making noises about it recently. i've not seen a graphics card that supports it from them yet, but i've not been paying attention so there may well be one.

The latest high-end PCI Express cards from NVidia support the technology (a quick search turned up with the 6600GT). I'm not really into the card numbers of NVidia but it's very likely you can find some more info on hardware sites.
SLI is only interesting if you're a die-hard gamer who wants to run everything at ultra-high. For anything else SLI is an overkill and too expensive because you need two high-end video cards and a motherboard with dual PCI Express.


I just ordered my new PC. It's a AMD Athlon 64 3500+(socket 939) pinned on a Asus A8V-E Deluxe motherboard and an Asus x800 Pro (ATI Radeon) with PCI Express.
Take note on the different sockets of the Athlon 64's. The athlon 64's use either a socket 754 or 939. The difference is that the 939 socket processors support dual channel memory which can result in a performance increase of about 5%. Thereby I read somewhere that AMD sees more future in socket 939 that 754. Thus the development of socket 754 processors might stop soon. So if you're planning on upgrading your processor in the future it's safer to go for a socket 939 processor/motherboard than a socket 754 processor/motherboard. But I advise to do some reading up on this all because I only learnt most of this two days ago when composing my own PC.

[Leshy]

Originally Posted by Structural Integrity

The latest high-end PCI Express cards from NVidia support the technology (a quick search turned up with the 6600GT).

Which is also the only new card from nVidia to be available in AGP format.

[meglamaniac]

A few corrections:

SLI in its nVidia incarnation has been around for several months now, and rumoured for a while before that as details of the nForce4 motherboard chipset were leaked.
Asus boards using the nForce4-SLI chipset have been "available" since November but realisticly are only just becoming available now (ie. orders are finally starting to ship). Other manufacturers will have SLI boards ready very soon or are launching them now.
VIA are also releasing an SLI chipset, which will make it onto cheaper motherboards. As it's not the "real deal", being reverse engineered from an nVidia technology which nVidia already provide (the nForce4) it's debateable how worthwhile it is. Logic would certainly suggest nVidia will always have the upper hand seeing as they dictate the specifications for both the nForce4 chipset and the GeForce 6 graphics cards - the two critical components.

Talking of graphics cards, both the 6600 and 6800 series support SLI, although it is highly recommended (even by nVidia) that you use two identical cards from the same manufacturer, which rather puts paid to the "SLI as an upgrade option" reason for buying - what are the chances of getting an identical card in a year's time?
On top of that, it's actually cheaper to buy a non-SLI motherboard and a GeForce 6800GT, or possibly even a 6800 Ultra, than it is to buy an SLI motherboard and two GeForce 6600GT cards. This means the only viable market for SLI is hardcore gamers with more money than sense, who think that a single 6800 Ultra isn't enough.

On the AGP point, both 6600 (GT) and 6800 (non GT, GT and Ultra) are readily available right now for purchase in AGP format. Other lower spec cards will follow when nVidia feel they've creamed the market for long enough.
It should be noted that all GeForce 6 cards are PCI-express native, so any AGP card is simply a PCI-e card with a bus translator stuck on it. This means the AGP cards will always be slightly slower, and run hotter (the bus translators are already becomming notrious for getting VERY hot), than their PCI-e counterparts.

I think thats about everything.

[mist]

i'm curious, how does antialiasing work on SLI? i thought it worked with the pixels around it, but won't the majority of those be being calculated by the other card?

[meglamaniac]

There'd be two possible solutions for that:
a) Pooled memory, where both cards have access to each other's RAM for certain ops. PCI-express is certainly fast enough for that - the PCI-e 8x slots used for SLI mode have 20Gb/s full duplex EACH available to them.
b) Proprietry nVidia commands across the SLI bus to allow one card to request an operation be performed on the other. The cards are linked by a small multi-pin connector so this is certainly a possibility.

However, the nVidia SLI does not work like the old 3DFX voodoo SLI did. With 3DFX, each card rendered alternate scanlines (ie. one did odds, one did evens) whereas nVidia splits the screen into a top and bottom half and each card is assigned one lump half of the screen.
This method has advantages in that it requires very little co-operative rendering for things like antialiasing, as the cards need only consult each other on the boundary line. The rest of the time they're only concerned with their section.

That'd be my guess anyway.

[wu_trax]

thanks for all the info. i guess i dont need sli then (and i dont have mony for that anyway).
I think ill take a board with a pci-e slot (AGP is more or less out of date now, isn't it?), an atholn 64 3500+, 1GB of ram and some geforce 6600 or 6800 (depending on how much money i have left)

[wu_trax]

Originally Posted by Structural Integrity

Asus A8V-E Deluxe

i can't get that board here
since we now have that funny money: where did you order, what did you pay and do you know any online-shops that deliver all across euro-land?
i saw the board at one shop for about 120€, but they don't get it until the 7th of febuary. My current PC is more or less broken, i get blue screens all the time, so dont want to wait that long

edit: found one for 139€, delivery in 3-5 days

[Structural Integrity]

Originally Posted by wu_trax

i can't get that board here
since we now have that funny money: where did you order, what did you pay and do you know any online-shops that deliver all across euro-land?
i saw the board at one shop for about 120€, but they don't get it until the 7th of febuary. My current PC is more or less broken, i get blue screens all the time, so dont want to wait that long

edit: found one for 139€, delivery in 3-5 days

I ordered everything at Salland. The delivery time of the motherboard just went up to 22 days . I'm considering to change my order at this moment.

[wu_trax]

Originally Posted by Structural Integrity

I ordered everything at Salland. The delivery time of the motherboard just went up to 22 days . I'm considering to change my order at this moment.

any idea about an alternative? the other one i found doesn't have it either. i guess its not even out yet. now i want one with pci-e, but can't find anything, at least none without SLI, i certainly dont want to buy two graphic cards

[Structural Integrity]

The MSI K8N Neo4 Platinum 54G and Gigabyte GA-K8NXP-9 are the only other motherboards on Salland that has a single PCI-Express slot and a socket 939.
Other boards are based on the NForce4 SLI chipset.

Neither of these boards have a delivery time of under 3 weeks.

For socket 754 I found on Salland:
Asus K8S-MX

That's it...

It seems that PCI-express isn't picking up as fast as I thought. I also searched www.tweakers.net for PCI-Express (Dutch) but not too much interesting releases turned up.
Big uncle Tom doesn't come up with any interesting information either. It seems that the main chipset makers with PCI Express are VIA with the K8T890, NVidia with the NForce4 and SiS with the SiS756.

[wu_trax]

same here. i found this one more here, the Abit AX8, but none of those with one PCI-e-slot seem to be available
in fact they hardly have any 939-boards at alternate.de at all i checked two other places, but none of them had anything yet

[Leshy]

Having a SLI-supporting motherboard doesn't actually require you to use two graphics cards.

[meglamaniac]

Oh and (this is one of the good bits about PCI-e) if you do get an SLI board you can still put smaller x1 card in the larger x16 aized slot, so you don't lose a slot.

[wu_trax]

Originally Posted by Leshy

Having a SLI-supporting motherboard doesn't actually require you to use two graphics cards.

oh, i didn't know that, but it still requires me to pay for it
anyway, the only one available here right now is the Asus A8N-SLI Deluxe and that one seems to suck (or at least someone said so in a comment on it)

[MrPubes]

I recently bought an AMD64 3200+, 1GB Ram, an Asus SLI Board, and one PCI-E 6600GT.
And in about a year or so i will buy another 6600GT. This seemed like the smartest move to keep in business cheap in a year. And by what i read it is possible to combine different brands of 6600GT's , as long as they are the same actually. The Club-3D i bought is based on the NVIDIA reference design. It shouldn't be too hard to find another one in a year.

[wu_trax]

what board did you buy? the A8N-SLI ? is it ok or did you have any trouble with it?

[MrPubes]

Yep, it's the Asus A8N-SLI.
Does a good job here.
No problems yet, rocksolid.

[wu_trax]

ok, if you say so ill give it a try
i really need a new one. 3-4 blue screens / freezes today

[wu_trax]

i got everything today \o/
asus A8n delux
asus n6600GT
1GB ram
athlon64 3500
2 80GB sata (or whatever, i have no idea about what i bought) hard disks for a raid
and a new power-supply thingywith 480W which is suprisingly quite.

i am so ****in happy now.

[djbass]

Originally Posted by meglamaniac

Oh and (this is one of the good bits about PCI-e) if you do get an SLI board you can still put smaller x1 card in the larger x16 aized slot, so you don't lose a slot.

Wouldn't the x16 slot already be taken by the video card. Most boards I've seen for SLI don't have two x16 PCI-e slots, rather for SLI mode they supply a bridge that connects between two x8 slots to privide the full x16 bandwidth required by the second card.

[meglamaniac]

No.
At the moment the only boards out there supporting SLI are nVidia based. The SLI boards have 2 x16 slots (see this image and this specification). However, when operating in SLI mode both slots disable half their lanes, becoming x8. I'm not sure what the reason for this is - it's likely to do with there simply not being enough lanes available on the PCI-e controller. More on that below.
Part of the PCI-e spec is that any PCI-e device has to be able to autosense the number of lanes available to it and adjust accordingly, so this does not provide a problem to the graphics cards - their bandwidth is obviously halved, but they don't really use the PCI-e bandwidth much anyway (they would if they used the system memory as well as their onboard memory, but at the moment no high end graphics cards do that because of latency).
The connector between the two cards is not, repeat is NOT, anything to do with PCI-e. It's a proprietry nVidia connection, presumably to allow the two cards to negotiate with each other without having to go through the PCI-e controller - allowing them to have a dedicated high-speed link all to themselves.

I also believe that the second x16 slot in all probability never has 16 lanes available to it. I suspect it has only 8 lanes but is x16 size simply to fit the graphics card in. The PCI-e spec allows for this too, it's perfectly acceptable.
So what is really onboard, I think, is:
* 1 x16 slot
* 1 x8 slot
* 3 x1 slots

It makes logical sense that the PCI-e controller probably has 32 lanes available to it (developers like to go with numbers that make sense in byte terms. If it had an odd number like 29 then that makes for translation headaches when implimenting the hardware). That means there are still 5 lanes available - they will be taken up by onboard devices (say 1 sound, 2 network, 2 firewire).
This would also explain why SLI operates at x8 - not enough available lanes for x16.

That's my theory anyway.
It'd be interesting to find a spec that backs it up or shows it's bullshit, but I can't find much in the way of technical details on an enginering level.