HELP: Mixing MSI 7950 with Sapphire 7950, will it work? :)

[cointrest]

Hi, I'm new here, wonderful community!  I'm mining litecoins and got myself a MSI 7950. However, all the 7950s have pretty much ran out already and I can't find anymore MSI's. I'm thinking of getting a Sapphire Vapor-X 7950 to go along with the MSI. Will this work? Will mixing it have conflicts on cgminer? Is it ok if I also mix MSI with Sapphire and Asus?  Thanks so much for helping!!

[cointrest]

Help, anyone? I'm waiting to order the Sapphire, don't want to get it wrong. If the question is really obvious or silly can you just please answer it though? Thanks so much.

[onthehunt]

The brand doesn't really matter in the sense that certainly the MSI & Sapphire will be fine together, just as the MSI & Asus or Asus & Sapphire would also be fine.

People just recommend brands they've had good experiences with, or what has better cooling and will survive overclocking and running 24x7 better, but this is all just based on peoples individual opinions. It would be hard to objectively tell them apart though because some people have really good experiences with one brand while others have the exact opposite experience, and so a lot of it is just hearsay.

Hope this helps!

[Zemou]

No problems mixing cards.

BTW, I own 4x Sapphire HD 7950 (Dual X) and they work perfectly with a nice O/C.

[cointrest]

True what you've said about the hearsay bit. I've heard a lot of mixed opinions so I wonder if anyone had tried mixing brands together and gotten it to work. I don't really mind getting my hands on any 7950 as stocks are so low and I've already made an initial investment on a MSI 7950. You helped, thanks for the reply!

The brand doesn't really matter in the sense that certainly the MSI & Sapphire will be fine together, just as the MSI & Asus or Asus & Sapphire would also be fine.

People just recommend brands they've had good experiences with, or what has better cooling and will survive overclocking and running 24x7 better, but this is all just based on peoples individual opinions. It would be hard to objectively tell them apart though because some people have really good experiences with one brand while others have the exact opposite experience, and so a lot of it is just hearsay.

Hope this helps!

Have you tried mixing brands or heard of anyone mixing brands and working?  Thanks for the reply!

No problems mixing cards.

BTW, I own 4x Sapphire HD 7950 (Dual X) and they work perfectly with a nice O/C.

[pening]

No problems mixing cards.

BTW, I own 4x Sapphire HD 7950 (Dual X) and they work perfectly with a nice O/C.

OK, at risk of hijack (though useful to the OP i'm sure), what do you get out of the Sapphire Vapor?  Scrypt i assume?  I've tried everything with one and i cant get above 560 KH/s (was ~600 MH/s under SHA256 for raw Bitcoin).  I am using a full width riser because it wouldn't fit in the PC (HP office box, free and with 4GB) but not sure why that would make a difference.

as for mixing cards, everyone says no problems, but i found the main card dropped significantly in output when adding a second.  use of un-powered risers might be an issue here, though i still don't get why power isn't transferred through the riser if its available and required by the card (which should surely just require the PSU input).

Back to the OP, in cgminer you just have to separate the settings for different cards using " ," between values, as they'll probably have different optimal clock and Intensity settings.

[cointrest]

Hey Pening, that is such a helpful reply!  I'm intending to get the Vapor X with boost so it should go up a little. I heard that Sapphires deteriorate in speed because of the heat so perhaps increase the cooling?  Please let me know if you solve the riser issue! 

Which cards do you mix with? Great advice on the cgminer settings. Do you know where I can find a tutorial for it or any other threads for it? Thanks so much! You save my rig! 

OK, at risk of hijack (though useful to the OP i'm sure), what do you get out of the Sapphire Vapor?  Scrypt i assume?  I've tried everything with one and i cant get above 560 KH/s (was ~600 MH/s under SHA256 for raw Bitcoin).  I am using a full width riser because it wouldn't fit in the PC (HP office box, free and with 4GB) but not sure why that would make a difference.

as for mixing cards, everyone says no problems, but i found the main card dropped significantly in output when adding a second.  use of un-powered risers might be an issue here, though i still don't get why power isn't transferred through the riser if its available and required by the card (which should surely just require the PSU input).

Back to the OP, in cgminer you just have to separate the settings for different cards using " ," between values, as they'll probably have different optimal clock and Intensity settings.

[dailybread]

Not a problem at all, im mining off 3 different series of cards in one machine.

[cointrest]

Cool Which do you use? Does that compromise on the speed though? They run as fast as the slowest one don't they? How do you set up cgminer, what are you configurations? Do you have a brief guide? Mind sharing with me, it'll help so much! Thank you dailybread!

Not a problem at all, im mining off 3 different series of cards in one machine.

[pening]

Hey Pening, that is such a helpful reply!  I'm intending to get the Vapor X with boost so it should go up a little. I heard that Sapphires deteriorate in speed because of the heat so perhaps increase the cooling?  Please let me know if you solve the riser issue! 

Which cards do you mix with? Great advice on the cgminer settings. Do you know where I can find a tutorial for it or any other threads for it? Thanks so much! You save my rig! 

There hasnt been a deterioration in speed, always been that way, about 100 Kh/s below what wiki mining says you can get.  under SHA256 i had the same issue.  i've put it down to the PC hardware because had the same with the another card, but i've also dont really know what im doing with the settings.  for example everyone seems to set the intensity to 19 or 20, but above 13 i spaff HW errors. 

the best tutorial is one by the author of cgminer, on this forum somewhere.  but the readme docs are very good too, and iirc theres some examples for two cards.  cgminer will simply recognise both cards and use them, if you want to tune their settings individually you set the values seperated by ",".

[killua123]

you should be able to use any cards with each other. (i think even nvidia and amd cards..) although if you require crossfire or sli then both need to be of the same but not of the same brand.. so 7950s all can be crossfired.. etc!

[cointrest]

You sound like you've been quite very productive!  Pening, do you have any examples on how you configured gpus of the different brands from the same series? I've looked around where you pointed but all I find are configs of 7970 and 7950 and different series    I really owe you one!

There hasnt been a deterioration in speed, always been that way, about 100 Kh/s below what wiki mining says you can get.  under SHA256 i had the same issue.  i've put it down to the PC hardware because had the same with the another card, but i've also dont really know what im doing with the settings.  for example everyone seems to set the intensity to 19 or 20, but above 13 i spaff HW errors. 

the best tutorial is one by the author of cgminer, on this forum somewhere.  but the readme docs are very good too, and iirc theres some examples for two cards.  cgminer will simply recognise both cards and use them, if you want to tune their settings individually you set the values seperated by ",".

[Zemou]

No problems mixing cards.

BTW, I own 4x Sapphire HD 7950 (Dual X) and they work perfectly with a nice O/C.

OK, at risk of hijack (though useful to the OP i'm sure), what do you get out of the Sapphire Vapor?  Scrypt i assume?  I've tried everything with one and i cant get above 560 KH/s (was ~600 MH/s under SHA256 for raw Bitcoin).  I am using a full width riser because it wouldn't fit in the PC (HP office box, free and with 4GB) but not sure why that would make a difference.

as for mixing cards, everyone says no problems, but i found the main card dropped significantly in output when adding a second.  use of un-powered risers might be an issue here, though i still don't get why power isn't transferred through the riser if its available and required by the card (which should surely just require the PSU input).

Back to the OP, in cgminer you just have to separate the settings for different cards using " ," between values, as they'll probably have different optimal clock and Intensity settings.

My cards are Dual X and not Vapor ones. And yes, I mine scrypt coins.
My cards mine at 620 khs, they can do better but my PSU is only 1100W so I wanted to stay around 1000W consumption to get the best PSU efficiency. So I lowered my voltage a lot. It's strange cause you should be able to easily reach 600 khs with your 7950.

BTW, I use powered risers for each card. I burnt the ATX pin before so I strongly recommend to ALWAYS use powered risers. I haven't got any speed deterioration (even for cards connected on x1 PCIe connectors). BUT I never noticed a speed deterioration using powered/unpowered risers.

[pening]

...
My cards mine at 620 khs, they can do better but my PSU is only 1100W so I wanted to stay around 1000W consumption to get the best PSU efficiency. So I lowered my voltage a lot. It's strange cause you should be able to easily reach 600 khs with your 7950.

Thanks for feedback.  Cracked it yesterday, i read on a forum a point about -g (lookup gap) value being 2 is wrong.  I've always used this for whatever reason, so i re-read the cgminer readme and it says don't touch it, its relevant only to low Intensity settings.  It dawns on me that this increases something at the expense of intensity, but with the trade off of a usable system - at I=13 you wouldn't know the machine is hashing even for 500-550 kh/s.  With -g 2 i could go above I=13 or 14 with out spewing HW errors. With -g 1 i can happily set to I=20.  now with threads pushed higher too im pulling 630 kh/s  woot!.

Lesson to OP:  read lots of forums (try searching card type/name + mining), read the damn documentation  and experiment, keeping records of changes and their effects.