PCIE 16x vs PCIE 8x - GTX 580

[UaVaj]

looking for a new motherboard for overclocking purproses.

CPU is a i5-760. obviously 1156 chipset family (P55) does not natively support SATA3 (6Gb/s) / USB 3.0. To have these two features, an add-on Marvel Controller is necessary.

The expense is - with SATA3/USB3 enable. The PCIE 2.0 slot that the gtx580 sits in will be reduces from 16x to 8x.

Will this reduction in bandwidth bottleneck the gtx580?



There are a few older reviews on 16x vs 8x and it shows a difference of 1-2%. however those GPU tested are much inferior compare to a gtx580.

 

[Necc]

Check This & This & This out!

 

[dagamer34]

The answer is a definitive no.

 

[UaVaj]

thanks necc (where is the thank you + contribution button?)

that is exactly what i am looking for. a gpu that is equalvent or faster than the gtx580.

at 1920x1200 going from 16x down to 8x. the 680 loss 4%. the 7970 loss 1%.

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a ~4% loss in video frame-per-second for a ~40% (175MB/s) gain in SSD performance. hmmm.

 

[UaVaj]

thanks dagamer34.

looks like pcie 2 - it is game dependant.

"Moving from PCIe 2 x16 (8GB/sec) to PCIe 2 x8 (4GB/sec) does incur a generally small penalty on the 7970. However like most tests this is entirely dependent on the game itself. With games like Metro 2033 the difference is non-existent, while Battlefield 3 and Crysis only lose 2-3%, and DiRT3 suffers the most, losing 14% of its performance. DiRT3’s minimum framerates look even worse, dropping by 19%. As DiRT3 is one of our higher performing games in the first place the real world difference is not going to be that great – it’s still well above 60fps at all times – but it’s clear that in the wrong situation only having 4GB/sec of PCIe bandwidth can bottleneck a 7970."

"Ultimately what is clear is that 8GB/sec of bandwidth, either in the form of PCIe 2 x16 or PCIe 3 x8, will be necessary to completely feed the 7970."

 

[Arachnotronic]

I have a suggestion for you:

Intel CPUs hold up resale value quite well. Sell your i5, and go with an IVB + Z77 board. It'll require a bit more of an investment, but it's worth it.

 

[UaVaj]

Intel17

thanks for the suggestion. since this is the boy's gaming rig. the cost difference ($150 for cpu + mb) is over the top for the minimal gain in gaming (4fps in bf3 n 6fps in crysis2).

i5-3570k w/ Z77 = ~300 OTD then SHIP (microcenter cpu+mb promo)
450mb/s ssd = ~120 SHIPPED (newegg)
vs
i5-760 w/ P55 = ~90+60 SHIPPED (used ebay)
275mb/s ssd = ~75 SHIPPED (used ebay)

price point vs intended usage - definitely staying with i5-760 and P55.

as for ssd performance or pcie performance. will decide on which poison to go with. chances are it will be the ssd. the difference between 450mb/s and 275mb/s will be less noticeable.