Motherboard choices

I made a thread about building my first PC here I pretty much have everything in order but I want to know more about motherboards.

As you can see, the one I initially had was for Core2Quad, 775 CPU. It was suggested I upgrade to i5 and DDR3, and it turns out it didn't cost much more to do so. So right now I have this mobo:

http://www.newegg.ca/Product/Product.aspx?Item=N82E16813128425

My main trouble is with the PCI express slots for GPUs. I want to eventually get two of the HD 5770's I plan on getting (Xfire), but I'm not sure what the whole deal is with PCI express slots. I can put two in that mobo, but I guess they both run at x8 instead having one at x16. I don't understand how that makes a difference. Also, there are other mobos I've been looking at like this:

http://www.newegg.ca/Product/Product.aspx?Item=N82E16813130239

just says it has two PCI express slots but mentions nothing of x16 or x8 etc.

Any clarifications and suggestions would be greatly appreciated.

With an socket 1156 motherboard (P55 chipset), when you're using two PCI Express slots, they will run at 8x and 8x.

8x and 16x is essentially how much data can be transfered through that slot. With a single GPU card like the 5770, running two cards at PCI Express 8x should not be a problem at all.

IIRC, the 8x transfer only becomes a problem when you want to run two Dual-GPU cards (I.e. 5970/GTX 295) at 8x speeds.

So what benefit do you gain by using two GPUs at x8 over one at x16?

grasshoppa said:

So what benefit do you gain by using two GPUs at x8 over one at x16?

Click to expand...

CrossFireX/NVIDIA SLI technology two GPUs 8x on LGA 1156 Intel P55 or two GPUs 16x on LGA 1366 Intel X58.

Or 16x/16x on LGA1156...

MSI Dual 16x LGA1156

Really though, the difference between 8x/8x and 16x/16x is less than 5% with current cards... and not worth the price premium, in my opinion.

MattNo5ss said:

Or 16x/16x on LGA1156...

MSI Dual 16x LGA1156

Really though, the difference between 8x/8x and 16x/16x is less than 5% with current cards... and not worth the price premium, in my opinion.

Click to expand...

16x/16x on LGA1156 Have you found a review on how that actually works on a Intel P55 + Lucid Hydra 200 chip set. the P55 only has 16x or 8x 8x there cheating the customer.

The NF200 chips add additional PCIe lanes by using the lanes of unused PCI slots. If you only have 2 GPUs and no other PCI devices, then there are unused lanes which the NF200 uses for the GPUs. That's what I get out of it.

PCIe And CrossFire Scaling: Does Nvidia's NF200 Fix P55?

MattNo5ss said:

The NF200 chips add additional PCIe lanes by using the lanes of unused PCI slots. If you only have 2 GPUs and no other PCI devices, then there are unused lanes which the NF200 uses for the GPUs. That's what I get out of it.

PCIe And CrossFire Scaling: Does Nvidia's NF200 Fix P55?

Click to expand...

We had a big debate over this with the senior members. I even sent two e mails to msi and no response yet.

QUOTE: MSI’s Trinergy motherboard represents the “standard” method for multiplying PCIe pathways through the NF200 bridge. All 16 of the processor’s PCIe 2.0 lanes are connected to the bridge, which is then able to control up to two cards in x16 mode or four cards in x8 mode. MSI provides its first slot with 16 of the NF200’s 32 lanes, while the second slot has eight fixed and eight switchable pathways. MSI’s third slot borrows eight pathways from the second slot via automatic mode switching whenever a card is installed, switching the board from x16/x16/x0 to x16/x8/x8.

See that's only 16x lanes coming from the 55 chipset, you would need 32 lanes from the 55 chip set.

I've done some more searching, and I was wrong in my last post. It doesn't use unused lanes...

The NF200 can output twice the amount of input lanes, 32 in this case.

MSI provides its first slot with 16 of the NF200’s 32 lanes, while the second slot has eight fixed and eight switchable pathways.

Click to expand...

Although, I don't know all of the intricacies of how it works exactly.

Here's a slide of the different NF200 configs on X58. It would work the same on P55.

MattNo5ss said:

I've done some more searching, and I was wrong in my last post. It doesn't use unused lanes...

The NF200 can output twice the amount of input lanes, 32 in this case.



Although, I don't know all of the intricacies of how it works exactly.

Here's a slide of the different NF200 configs on X58. It would work the same on P55.

Click to expand...

The only way I think that can work is if the NF200 chip alternates back and forth to each bus card slot with the 16x lanes that's kind of cheating.

not sure if i should say thanks wingman, this is stuff i have already known. i tried to make it clear in that other thread how the NF200 is connected, MSI's blurb is exactly what i said. it is not surprising after reading that tom's article that P55 with SLI/CF was faster then a NF200 with SLI/CF. simply because there was added latency to the overall PCIE buss by using a NF200 connected to the cpu's PCIE lanes. since the NF200 has to then copy the data to be sent to both gpus(when in sli). If not in sli then it would just route the data/info to which gpu is suppose to get it. i cant really say that in a 3way CF/SLI setup that i would go with P55+NF200, X58 would be a better choice even if 16/8/8 configuration. what companies are doing with a NF200 setup is cheating the customer,IMO. Though im not the guy that designed or marketed the board. i just dont get why some would pay $300+ for a LGA1156 board when X58 has more things going for it then P55. this isnt to start a debate about the LGA1156 cpus but the overall platform has many limitations people need to keep in mind vs LGA1336.

IMO a single gpu has more then enough power for 90% of the people out there gaming. saying your going to go sli later is really not saving you any money. when you consider you can resell your card and put that with what ever you were going to spend to get a better single GPu card.

*maybe i missed something in my post, im not sure. i see/think of it i will post it later.*

Thanks for your response, IMHO also think they are cheating the customer due to the speed tested at toms hardware. NF200 chip causing a delay form copying 16x lanes into 32x lanes.

That would slow all quad sli or crossfire down because the slowest rendering card is off the NF200 chipset, the rest of the cards wait on that NF200 chip. even though vista and windos7 has a frame buffer of much more then 3 frames that XP has, I still would not want such a big buffer delay or dropped frames.

Nvidia IMHO is just cheating the customers with MSI p55+NF200 chipset also quad sli because of the NF200 chipset period.

IMHO I also think Quad SLI or crossfire is a waste in 16x16x two GPU's per card anyway, because of the delay and all the extra frame buffering.

I also agree one GPU is the best 90% of the time. A dual on the same card is ok to, there is less latency then on dual slots, it's minimal but it's there. IMHO big frame buffering is cheating the customer. Using more then two GPU's causes big frame buffering.

EDIT:here is a diffrent test.
well in this bench test the native p55 chip set did much worse than the NF200+P55 chip set and not to bad with x58 chipset.
PCIe And CrossFire Scaling: Does Nvidia's NF200 Fix P55
LINK:http://www.tomshardware.com/reviews/p55-crossfire-nf200,2537-2.html

Personally, i like the intel motherboard systems. For me, i understand the bios alot easier, and the diagrams are easily accessible on the intel.com site. And as for upgrades, intel is great at giving them away for free.