Bitcoin Forum

Bitcoin => Mining => Topic started by: Blackasaurus on April 06, 2011, 01:19:55 PM



Title: Second slot at x8 or even x4?
Post by: Blackasaurus on April 06, 2011, 01:19:55 PM
If I have a motherboard with a second vid slot running at x8 or x4 instead of x16 will it have a large impact on my mining speed?


Title: Re: Second slot at x8 or even x4?
Post by: cdb000 on April 06, 2011, 01:21:25 PM
If I have a motherboard with a second vid slot running at x8 or x4 instead of x16 will it have a large impact on my mining speed?

No impact at all.

My biggest mining machine has 4 cards, 1 at *16, 1 at *8 and 2 at *1.
There is no difference in mining speed between cards.


Title: Re: Second slot at x8 or even x4?
Post by: allinvain on April 06, 2011, 01:59:02 PM
second poster is definitely right..bitcoin mining is NOT bandwidth (PCI express bandwidth) intensive so it doesn't really matter how many PCIE lanes you have.


Title: Re: Second slot at x8 or even x4?
Post by: Alexium on April 06, 2011, 02:09:36 PM
second poster is definitely right..bitcoin mining is NOT bandwidth (PCI express bandwidth) intensive so it doesn't really matter how many PCIE lanes you have.
Does it mean no penalty at all even on fastest cards @x1? Say, 5970 @ x1?


Title: Re: Second slot at x8 or even x4?
Post by: [Tycho] on April 06, 2011, 02:14:47 PM
second poster is definitely right..bitcoin mining is NOT bandwidth (PCI express bandwidth) intensive so it doesn't really matter how many PCIE lanes you have.
Does it mean no penalty at all even on fastest cards @x1? Say, 5970 @ x1?
Perfectly fine. Some people use flexible PCIe x1 extenders to install 4 cards in one MB.
x1 is even more than enough.


Title: Re: Second slot at x8 or even x4?
Post by: Alexium on April 06, 2011, 02:19:23 PM
Some people use flexible PCIe x1 extenders to install 4 cards in one MB.
That's what I was considering, thanks :)


Title: Re: Second slot at x8 or even x4?
Post by: [Tycho] on April 06, 2011, 02:30:15 PM
Some people use flexible PCIe x1 extenders to install 4 cards in one MB.
That's what I was considering, thanks :)
Not all extenders are flawless, some may not work. But some are fine :)
And you may need to shorten a couple of pins for MB to detect card's presence.


Title: Re: Second slot at x8 or even x4?
Post by: Blackasaurus on April 06, 2011, 03:15:57 PM
Thank you all

I was thinking of adding a second card to my system and thought I would have to buy a new motherboard  ::)


Title: Re: Second slot at x8 or even x4?
Post by: allinvain on April 07, 2011, 04:30:30 AM
second poster is definitely right..bitcoin mining is NOT bandwidth (PCI express bandwidth) intensive so it doesn't really matter how many PCIE lanes you have.
Does it mean no penalty at all even on fastest cards @x1? Say, 5970 @ x1?
Perfectly fine. Some people use flexible PCIe x1 extenders to install 4 cards in one MB.
x1 is even more than enough.

Heheh..yeah that's possible but it certainly would be a ghetto setup. But the again it's cheaper than buying a suitable motherboard.

Another problem with motherboards that feature 4 PCIE slots (x16 or x8) is the spacing. One solution would be to install a water cooling block on all 4 cards :) Imagine 4 5970s or 5870s  ;D


Title: Re: Second slot at x8 or even x4?
Post by: Zamicol on April 09, 2011, 09:04:03 PM
second poster is definitely right..bitcoin mining is NOT bandwidth (PCI express bandwidth) intensive so it doesn't really matter how many PCIE lanes you have.
Does it mean no penalty at all even on fastest cards @x1? Say, 5970 @ x1?
Perfectly fine. Some people use flexible PCIe x1 extenders to install 4 cards in one MB.
x1 is even more than enough.

So would something like this work? 
http://cgi.ebay.com/StarTech-com-PCIe-X1-X16-Slot-Extension-Ad-PEX1TO16R-/300545732681?pt=LH_DefaultDomain_0&hash=item45f9ebf049#ht_1204wt_1141
 (http://cgi.ebay.com/StarTech-com-PCIe-X1-X16-Slot-Extension-Ad-PEX1TO16R-/300545732681?pt=LH_DefaultDomain_0&hash=item45f9ebf049#ht_1204wt_1141)
I'm thinking about upgrading my mother board, but it is always nice to look at all the other options.  :)


Title: Re: Second slot at x8 or even x4?
Post by: burtyb on April 11, 2011, 09:42:15 AM
So would something like this work? 
http://cgi.ebay.com/StarTech-com-PCIe-X1-X16-Slot-Extension-Ad-PEX1TO16R-/300545732681?pt=LH_DefaultDomain_0&hash=item45f9ebf049#ht_1204wt_1141
 (http://cgi.ebay.com/StarTech-com-PCIe-X1-X16-Slot-Extension-Ad-PEX1TO16R-/300545732681?pt=LH_DefaultDomain_0&hash=item45f9ebf049#ht_1204wt_1141)
I'm thinking about upgrading my mother board, but it is always nice to look at all the other options.  :)

Unless you have a 1U server I doubt it - the socket is at a right angle so the card would be directly over the MB - not sure if there would be enough height for double slot cards either.

I went for the option of cutting a slot in the end of the PCIe slot which keeps it the same position and the card still fits in the case properly.

Chris.