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Alternate cryptocurrencies => Mining (Altcoins) => Topic started by: taj on January 29, 2014, 12:14:09 AM



Title: Board influences the hash outcome?
Post by: taj on January 29, 2014, 12:14:09 AM
So this is my question...

I've read somewhere people posting hardware that works good together and what doesn't.. does it really matter?

I have a 70 euro mobo and cpu (F2 A55-M LE and the cheapest amd cpu out there) combo with two R9 290x doing 740 stable kh each. Now I'm waiting for two R9 290 and I'm wondering what board should I get.. I'm thinkinh about buying the same combo... but also I think my R9 280x could get like 770 kh and no idea if its board related...

would enjoy some input and opinions about this

thanks


Title: Re: Board influences the hash outcome?
Post by: Gator-hex on January 29, 2014, 12:23:54 AM
You need M/B and CPU that support PCI 3.0 or you won't get the best speed.

I saw 30% performance boost moving from a Core 2 Quad PCI 2.1 system to i5 PCI 3.0 system with the same graphics cards.

The data bus is just faster on newer M/B and CPUs. I see people put a cheap Celeron CPU on a decent 3.0 M/B all the time and it's just slow!


Title: Re: Board influences the hash outcome?
Post by: taj on January 29, 2014, 12:41:41 AM
so, by PCI 3 support you mean at least a sandy or ivy? Amd didnt supported PCIe 3 last year i think now I dont know... anyway I've read people telling that even if it was possible to use a pcie16x card in a 1x slot it wouldn't matter for the outcome. You have any sources or any place I could read abou it?


edit: so ive been reading and what i read earlier was just dumb people, pice3 have actually a much bigger bandwitch than the pcie2 and it can increase the overrall graphic performance


Title: Re: Board influences the hash outcome?
Post by: crazyates on January 29, 2014, 05:52:01 AM
You need M/B and CPU that support PCI 3.0 or you won't get the best speed.

I saw 30% performance boost moving from a Core 2 Quad PCI 2.1 system to i5 PCI 3.0 system with the same graphics cards.

The data bus is just faster on newer M/B and CPUs. I see people put a cheap Celeron CPU on a decent 3.0 M/B all the time and it's just slow!

If PCIe 3.0 is twice as fast as PCIe 2.1 because of the added bandwidth, then how come I see a ZERO drop in hashrate when I mine with my GPUs plugged into the MB, using all 16x PCIe lanes, or when I'm running them off a 1x to 16x riser?


Title: Re: Board influences the hash outcome?
Post by: taj on January 29, 2014, 11:48:04 AM
that what i was going to ask now, because even if that is true, how you explain all the people using razer cables plugged in x1 without any drops in hashrates...

anyway... so Ill probably buy the same conf, amd a4-4000 and asus a55m le...

in the meanwhile if anyone have any idea on how to increase the hashrates of my two R9 280x from 720/730 to 770 tell me something.

i use
core 1055
mem 1500
flashed bios voltage on both of them to 1130 (tried to flash them to 1100, 1110 and 1120 but they didnt kept stable)
gpu threads 2
gpu power 20
thread concurrency 14336
fan 100%

my temperature are in one card 54 and other 64...


Title: Re: Board influences the hash outcome?
Post by: Wipeout2097 on January 29, 2014, 02:56:16 PM
You need M/B and CPU that support PCI 3.0 or you won't get the best speed.

I saw 30% performance boost moving from a Core 2 Quad PCI 2.1 system to i5 PCI 3.0 system with the same graphics cards.

The data bus is just faster on newer M/B and CPUs. I see people put a cheap Celeron CPU on a decent 3.0 M/B all the time and it's just slow!

If PCIe 3.0 is twice as fast as PCIe 2.1 because of the added bandwidth, then how come I see a ZERO drop in hashrate when I mine with my GPUs plugged into the MB, using all 16x PCIe lanes, or when I'm running them off a 1x to 16x riser?
To be frank, you're not contradicting him. Your PCI-e risers still provide dedicated lanes, with the same PCI-e version

It could be so many things, including high PCI-e latency, collisions or crappy hardware attached to the bus ( integrated sound, sata, ethernet )


Title: Re: Board influences the hash outcome?
Post by: crazyates on January 31, 2014, 01:11:31 AM
You need M/B and CPU that support PCI 3.0 or you won't get the best speed.

I saw 30% performance boost moving from a Core 2 Quad PCI 2.1 system to i5 PCI 3.0 system with the same graphics cards.

The data bus is just faster on newer M/B and CPUs. I see people put a cheap Celeron CPU on a decent 3.0 M/B all the time and it's just slow!

If PCIe 3.0 is twice as fast as PCIe 2.1 because of the added bandwidth, then how come I see a ZERO drop in hashrate when I mine with my GPUs plugged into the MB, using all 16x PCIe lanes, or when I'm running them off a 1x to 16x riser?
To be frank, you're not contradicting him. Your PCI-e risers still provide dedicated lanes, with the same PCI-e version

It could be so many things, including high PCI-e latency, collisions or crappy hardware attached to the bus ( integrated sound, sata, ethernet )
How am I not contradicting him? He said that PCIe 3.0 will get you higher speeds, because of the higher bandwidth.

PCIe 2.0 offers 500MB/s per lane, or 8GB/s for a 16x slot.
PCIe 3.0 offers 1GB/s per lane, or 16GB/s for a 16x slot.

So if my cards run at the same hashrate, no matter if they're running on a PCIe bandwidth of 500MB/s or 8000MB/s, why would I need to upgrade to PCIe 3.0 to run them at 1GB/s (a 3.0 1x riser cable)?

It could be PCIe latency, which is something I'm looking into lately. Collisions? Nope. PCIe isn't like the old PCI slots, where everything was parallel and shared a bus. Each lane is a dedicated line right to the controller.