PCI-E 16x vs. 4x

Gary_Busey

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How big of a performance difference is there between 16x and 4x? I'm looking at getting this board to upgrade my old system, and it looks like it'd make a good modest transition to newer tech, while still allowing me to use my old ram, drives, and video card:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157107

I've read that it's PCI-E slot is only 4x. How big of a performance hit would I take compared to a 16x slot?
 

blade85

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well a 4xpci-e is like an 8x AGP, sooooo you do the maths :p

cards upto the 1950xt will run with very little difference. Though im not sure i can say the same for the 8800 or 2900 cards :?
 
I'm not sure where they got 4x. newegg says it's 16x and other sites I've seen say the same thing. Reviews I've seen say it works well with the 8600 series cards, so it seems like it would be fine. I don't know the exact numbers, but current GPUs don't use the full 16x bandwidth provided by that lane. I don't think you will run into any problems. Worst case scenario, you buy a card, it doesn't work, you send it back and drop down a level. Also, the board has AGP so you could still get an X1950 for decent performance.
 

blade85

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iv got an asrock 775 dual vsta, and that has 4x pci-e aswell.

I think there are 2 more boards including the one the OP posted that are 4X pci-e + 8X AGP
 

dsidious

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There was an article on this subject on Tom's some time ago. The difference between 4x and 8x was huge, then between 8x and 16x there was a rather small difference. I think they played with an 8800 GTS 320, if I remember right.
 
Yeah that would be this;

http://www.tomshardware.com/2007/03/27/pci_express_scaling_analysis/

It depends alot on card memory management and the application used and settings as to the effect.

Overall not huge, but noticeable in benchies. And the DX10 host-vpu relationship is still unknown, especially for future considerations like physics.
 

Gary_Busey

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Well, I'm planning on getting an E6300 but I still want to use my DDR400 memory for now. I have an AGP card, but if need be, I can sell it and buy the same card in PCI-E version. Which one of these boards would you guys reccomend?

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010200280+1387927201&Subcategory=280&description=&Ntk=&srchInDesc=

I could always go with an AMD setup too, but I don't know if it'd be as cost effective.
 
Mediocre options due to your constraints, while ECS is mediocre quality if it's full width PCIe, you might want to go that route. The ASRock one is nice, but you may eventually want to upgrade.

Find out if the ECS is full 8-16X speed, and go with that one, otherwise I'd say the ASRock is a good mid-term solution, and when you resell it to someone with an old X800/GF6800 AGP card upgrading from their S939 board or something then it will have higher resale value.

Tough call because of course nothing will be a 'gem', but the ECS may be slightly more competant. But just a guess.
 

jeff_2087

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I think the Asrock 775Dual or the PC Chips board is your best bet. The Asrock has PCI-e, but your graphics card is pretty good and by the time it needs to be replaced PCI-e x4 might be pretty useless anyway. But I haven't heard anything about PC Chips boards, they might be total stinkers.

Asrock with an e4300 would be a good upgrade if you really want a new CPU. The P4 3.0 is far from ideal, though not totally obsolete.
 

jeff_2087

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e6300 does have an extra 60 MHz but unless you've got a good board the e4300 is a better overclocker. Since the 4CoreDual-VSTA's FSB goes up to around 300 or a bit more from what I've heard, you couldn't get much of an overclock out of the e6300's 266 FSB. But the e4300's 200 FSB could let it approach 3GHz.
 

jeff_2087

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Well you'd probably have to use a ratio on the RAM unless you're doing a mild enough OC and the RAM is decent. I don't know what overclocking is like on the 4CoreDual but if has manual control over the timings you could probably clock the DDR400 higher and loosen the timings. Or just use a RAM ratio and keep it around 400.
 

jeff_2087

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Okay then, if it doesn't let you control memory timings you'd have to use a RAM ratio. It should have that because it can support a 1066MHz bus on DDR400.
 

Gary_Busey

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True. Either way, I think the only way I'd be better off getting a 6300 would be with a nicer board. With the ASRock board, the e4300 makes more sense.
 
I like your choice of the ASRock, and since unforunately the 4X is unknown, I don't want to promote it for a long term build, but IMO, personally, by the time it matters, hopefully the other component are cheap enough and you can get some cheap DDR2 and roll that mobo for almost what you pay for it (IMO it will keep value for a while longer than the ECS) and then you can concentrate on the bandwidth for whatever future card you have.

I would say the likelyhood of it having a big impact is minimal (as in you may see fps numbers change, but it's only below 4X that they become unplayable usually), but like I said DX10 and physics are a huge unknown.

I like the ASRock I think it's a good choice, good luck with the build, eh!
 
I've just changed from a 775 Dual Vista (the precursor to the one you are looking at) to a P5B DL Wireless.

No change in 3d mark06, still scoring about 5500 with a 7900GTO even when I changed from X4 to x16.

Have yet to test it with BF2, where I know roughly what sort of FPS I was getting, a real game might give a different result.

As an interim board to give you access to DDR/DDR2 and PCI-E/AGP its really good, was fairly happy with it.
 

Gary_Busey

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I agree. When the time comes, I'll buy a PCI-E card and see what happens, and then go from there. For now, my X1950Pro paired with an e4300 should show some considerable improvements over my current P4, hopefully.
 
Like I said its not a bad board, it does what it says on the tin.

I've only got rid of mine as the SATA controller was playing up and failing to recognise the HDD until about the 6th boot attempt. Other than that it was great, it brought me breathing space away from high DDR2 prices and expensive PCI-E cards.
 

Gary_Busey

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Like I said its not a bad board, it does what it says on the tin.

I've only got rid of mine as the SATA controller was playing up and failing to recognise the HDD until about the 6th boot attempt. Other than that it was great, it brought me breathing space away from high DDR2 prices and expensive PCI-E cards.
Awesome, that's pretty much what I'm looking for.