Can you explain how a motherboard works?

[SkScotchegg]

Hey there, I was wondering if you could please try and explain to me how a motherboard works. When I view them on OCUK, and I read the specs, I dont know what am looking for? I can't tell what is good and what isnt.

So mainly in this post I was hoping you could help me to read specs.

Tell me what to look for etc.


Thanks allot,


SkScotchegg

 

[Starfall]

How does it work....?

That's a pretty hard question!

It might be better if you could give and example of where your confused, for example give two motherboards in your price range.

 

[SkScotchegg]

Well I am wanting a motherboard that supports duel x16 PCI-express so I could run two graphics cards along side each other using SLI or crossfire for twice the speed.

Any chance you can post me some links to some of the best motherboards on OCUK that can do this?

I dont really have a price range, just want to know which ones can do the job. I'm not going to be buying my new system untill january though. But am wanting to pick it out now.

Cheers in advance,

P.S. Someone said that dual x8 lanes was no good and I should get dual 16x lanes? what do you think?


SkScotchegg

 

[mdjmcnally]

Don't pick out the parts now if buying in January. In the PC market there is always something around the corner and what is a good buy now isn't neccessarily what you would buy 4 months later.

 

[Tetras]

Any chance you can post me some links to some of the best motherboards on OCUK that can do this?

Firstly I'd say you have made a false assumption that SLI or Crossfire offers twice the performance, it doesn't. On a good day it can offer near this sure but on a bad day you'll get nothing or considerably less than half for double the price.

Unless you have a very large monitor chances are you don't need SLI/Crossfire and with few exceptions you are better off with a single card from both a performance now and future performance point of view, because by the time you come to upgrade there will be a faster single card than the previous generation you want another to pair it with (or another DX version or other feature(s) that makes it obsolete if not from a performance to price ratio point of view). It also uses double the power, heat output and space in the case that means you need a meaty power supply, plenty of room and decent cooling and it isn't a reliable performance boost.

Also as mdjmcnally says you are wasting your time picking parts now cos January will be a different market, 4 months is a long time in computer hardware!

All that said and the obligatory SLI/Crossfire avoidance warning:
The first obstacle to SLI/Crossfire mode are the graphics cards. For SLI you (to my knowledge it is still the case) need two identical model nvidia cards (though manufacturer can be different) and for Crossfire it depends on the generation but you firstly need two ATI cards and may need a master / slave configuration which requires a specific "master" card and a regular card (as the slave) or may not need this at all if it is more recent (check out the ATI Crossfire page: www.ati.com/crossfire).

The second obstacle is driver support and that is the main reason behind the exclusive Crossfire or SLI support boards have. You can find hacked drivers for a few boards (like Intel 975X) to run SLI for older cards but afaik no recent drivers exist that support 8800 series cards on any non-SLI chipset. It is also one of (if not the) main limitation of Crossfire/SLI performance that exists and one of the things that makes it look a poor choice value wise. Depending on the game you may get a considerable performance boost or you'll get next to nothing and for the trade-off in price, heat output and power consumption it isn't usually worth it unless you really need that extra performance.

Next you have the physical and electrical limitations of the chipset. Every chipset only has a limited amount of PCI-E lanes available to it and if it doesn't have enough for two graphics cards it won't support it, period. The same applies if you physically only have PCI-E 16X length slot, you aren't gonna be fitting two cards. The difference between physical and electrical is that the physical size of a 16X slot is what graphics cards are built for while electrical can vary even though physically the card fits. Many boards will not support two graphics cards running at 16X electrically and may reduce the lanes to 8X and 8X or 16X and 4X. The performance hits in reduced each mode vary between models and slot configurations and will continue to each time a new high end is released. If you want specifics you will have to look up the benches but generally 8X, 8X is not a significant performance hit over 16X, 16X and faster than 16X, 4X (depending on driver support).

Boards that support Crossfire on LGA775 are (mostly) Intel P965, P35 (16X, 4X), 975X (8X, 8X) X38 (PCI-E 2.0, 16X, 16X) and AMD/ATI RD600 (8X, 8X).

SLI on LGA775 = nvidia 680i (16X, 16X), 650i (8X, 8X).

 

[w3bbo]

Ok, here goes.

SLI and crossfire, though essentially the same thing will only work using a particular chipset depending on whether you want to use Nvidia (SLI) or ATI/AMD (Crossfire). An SLI setup won't work on a crossfire board(unless you used out of date hacked drivers) and crossfire wont work on an nvidia based board. When I say nvidia or ATI board I am not referring to the manufacturer of the motherboard but the chipset, which is in effect the brains of the motherboard. Crossfire chipsets are inherently intel chipsets where as SLI chipsets are Nvidia - confused? You will be! Nvidia are planning a new chipset that will be intel based yet run SLI but not crossifre (790i) - its only rumours atm though.

Now here is the quandry.

At the moment Intel make the best and more often than not fastest chipsets.
Nvidia make the best/fastest graphics cards.

The current line up of GPU's really don't make that much use of 16x pcie and will work fine in 8x.

If you are an avid gamer where fps counts for everything then I would go with an Nvidia based board and use an SLI setup say 2x8800 ultras. If CPU clockspeed and hard drive controller speed are more your bag then intel is the way to go.

Most chipsets are intel so you have a wide choice depending on your processor choice. the P35 and new x38/x48 based chipsets are an excellent choice for both dual and quad core and are also compatable with intels yet to be released 45nm penryn core cpu's. The P965 chipsets are still worth a buy if you are planning on using dual core, especially the asus p5bdlx which is possibly the most popular along with the gigabyte ds3. Give 975x a miss as its slower than 965 and cant match it for fsb but does have a great memory controller.

For Nvidia there is really only a couple of boards I would recommend and they are the reference 680i boards (BFG/XFX/EVGA) or the Asus striker extreme, also 680i based. These will get you the highest framerates when coupled with a pair of ultras but they are costly and in my experience would not push quad core aswell as p35 based chipsets. For dual core they match intels 965 chipsets for FSB and got my e6600 to 4 gig.

If you are buying in January the choices will have changed as Nvidia will have released the 780i chipset based boards and intel the x38/x48 based boards so unless you are buying now then I would keep a close eye on whats due to be released and make your decision based on that info rather than the info above.

 

[SkScotchegg]

Ok I have a couple more questions, but first I want to say thanks to everyone that has replied especially "Tetras" & "w3bbo" who both wrote those extensive responses to my post. You've cleared all this up for me, because I was confused about the SLI/Crossfire scene for quite some time.

Can I just say though, one of you mentioned if I have a big monitor it would be worth it? What did you mean by this? Because I am actually planning in the future to buy a big monitor, lets say 30" or around that size. So does a big monitor bring your performance down? Can you explain how that will effect things for my PC?

And also, the last thing I have to ask is, well let me explain, my PC is so old, its like 7 years old or something, I dont have an exact date, but even though its so old, and in that time I have only upgraded the graphics card, nothing else. Yet it still runs bioshock and crysis...

So my point is, you guys mentioned above I should wait for january, but I dont want to spend lots of money then on the latest hardware, what I am thinking is if I pick the parts I want now, and buy them in four months time, then surely they will be cheaper, and also, anything I buy is going to be faster then my currect PC isnt it? surely?

I mean, my CPU, RAM, mobo, must all be worth nothing, they're so old.....AMD 64 3000+ 1gig pc3200 ram, asus delux mobo all 7 years old.

So am just thinking I could pretty much buy any mobo, cpu and ram now, within reason, and its going to bascially kick a***.

Don't you agree?

P.S. I just have to say, this PC has been amazing and its lasted so long, and I dont know how its managed it, when I got the new graphics card x1950 with 512mb onboard memory it really increased my games speed by 50%, going from a radeon 9800 pro previously. I cant believe how long this PC has lasted and how well its served me. Never given me much of a problem or anything. It was there for me when half life 2 came out, and its still there for me now with crysis, (I have the beta ). What more can you ask? All I can say is, amazing!


SkScotchegg

 

[Tetras]

When we said about January it was in response to this:

I'm not going to be buying my new system untill january though. But am wanting to pick it out now.

There is no point picking parts now when you buy in January because by then there will be new stuff out and what is a good buy now may not be then (or even still available at all). There is a lot of new tech planned between now and for Q1 2008 so making a cast-iron spec for January, today, is silly.

Can I just say though, one of you mentioned if I have a big monitor it would be worth it? What did you mean by this? Because I am actually planning in the future to buy a big monitor, lets say 30" or around that size. So does a big monitor bring your performance down? Can you explain how that will effect things for my PC?

The reason for that is because there are no graphics cards that can handle DX10 games at max settings at 2560x1600 resolution (default of 30" screen). To get any decent performance at all with a monitor of that size you are prolly gonna have to go SLI or Crossfire and it is one of the few cases where when buying new, two cards makes sense.

For those at lower resolutions (smaller monitors) a single card is enough and it wouldn't be cost effective to get two lesser ones because of the unreliable performance increase SLI and Crossfire produce (and the heat output, power draw and space issues).

If you are going 30" then you are going to be on the bleeding edge of hardware for the life of the monitor cos I can't see the average resolution catching up to anywhere near that level. At the mo midrange and low high end seem optimised around 1280 x 1024 (19") and high end up to 1600 x 1200 (though even a GTX can struggle at that res in games like bioshock with maximum settings).