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Hey guys,

Just had a quick question. My motherboard is going out on my current PC. I'm getting a 8700k (16 Lanes), coming from a 4930k (40 Lanes). Since I have a dual 1080ti set up, will moving my GPU's from 16x to 8x cause any significant drop in speed?

Thanks!

At 8x, you will still be groovin'. Even at 4x most stuff zips along pretty decent, except the really heavy scenes of many GBs.. It is when you are down on 1x (either directly on mobo or using risers/splitters etc) that things start to suck big-time, from what I have read.

But if you do lots of animation, keeping 40 lanes would likely pay for itself pretty quick. I would certainly try to find a way to not downgrade my lanes...

Hey thanks for the reply!

Honestly, I'd love to keep the 40 lanes but this motherboard is done for. Right now, Intel doesn't have any 7th* Gen processors that can house two 16x cards for any cheaper than $800. Not only that but moving to x299 means more expensive motherboards as well. I just upgraded to 1080ti's in March.... I really want to do it but I can't

So, people that have 4 or 8 cards set ups run all their cards in 8x and 4x, respectively? I've always wondered how those set ups worked.

Can't you just find a replacement x79 mobo, if you are looking to not spend a pile right now?

Is your mobo actually totally dead, or do you think it is about to buy the farm?.. If things are simply acting up some, it could possibly be the PSU...

It's defintely not the PSU or SSD, those are new. I'm almost certain it's the Motherboard. It shuts off randomly, sometimes it won't post or recognize my drives. The other day I got a few blue screen of death for no reason. I've had to reinstall windows 3 times now because its just not working correctly. It works (Kinda) but the OS is still acting weird and I'm afraid to do any work on it now, Lol!

Anyways, yes, I did consider just getting a new x79 board but one from a good brand is the price of a new 8700k. I'd hate to spend that money and be wrong. I honestly just want a clean slate. I definitely don't want to spend any more, but I figured If I can move up 4 Generations for less than $800, I should just do it and pay for it with a freelance job down the road. Lol.

I'll still be keeping all the old parts, maybe even re-purpose them into a dedicated render machine, but it's time to move on to a newer daily driver. Especially if 8X is 99% of the performance of 16X, I think can live with that.

Well, I believe 8x is exactly 50% the performance of 16x... But the bandwidth is so high on PCIE, that unless you are talking high GBs, it just pumps into GPUs pretty damn quick. So 8x is okay for stills and light animation work, but if your bread and butter is animation, especially heavy scenes, you really need 16x, at all costs, on every last GPU, imho.

To be clear; PCIE bandwidth only matters during loading of stuff into GPUs. It has no effect on Ms/sec during rendering. Many animations do not require a reload on every frame, but many do, like anything with deformations etc.

I don't know the total specs on 16x vs 8x, but I do have 2 rigs, one with an Asus X99 E-WS running 4 cards at 16x and another rig running a Gigabyte Gaming 9 Z270 running 4 cards at 8x with the motherboards PLX chip.

I do animation and I don't notice a difference in daily work jumping between the two.

This article from Puget show's there isn't really a difference either: (though to be a better test, running an animation sequence on the identical card at 16x and 8x would be a more accurate representation)
https://www.pugetsystems.com/labs/artic ... s-x16-851/

All in all, if you wanna save some beans, don't sweat the 8x.

Yo, thanks for solid real-world info on 16x vs 8x. My info was purely based on my understanding that high-end-heavy-hitter-animation-types really needing that 16x for their work. Maybe things start to become noticeable at 4x. With my 28 lanes, I run at 8x, 4x, 4x, and often the real heavy scenes seem to take an eternity. I'm all SSDs too, so that is not likely a big bottleneck.