Best Hash/Watt GPU Setup, Undervolting

[carly200]

i am still deciding which board/CPU kombination..

going with AMD, I might go for Asrock 970 Extreme 4

but should I go with Sempron 145 or X2 180/190 ?

[Prelude]

Whatever is cheaper. Again, CPU makes zero difference to GPU mining.

[carly200]

i stumbled onto two other things that I was unaware before... slightly off topic, but maybe someone can give a quick answer

* Dummy plugs for GPUs if no display is installed: still needed, or solved with newer AMD Catalyst drivers?  (Win/Linux)
(if required, what is there proper name to look in electronics shop)

* RAM requirement for Litecoin: Does scrypt mining require a certain amount of RAM? (or was that due to bugs in the miner software?) how much?
* if RAM is required, does Speed/CL-timings make a difference?




(PS: Sempron 145 with possible/probable option to unlock 2nd core sounds good; any reasons not to go with ASROCK 970 extreme 4?)

[BitcoinHeroes]

Whatever is cheaper. Again, CPU makes zero difference to GPU mining.

CPU is still good to mine those CPU and not so GPU efficient coins like primecoin....

[Prelude]

i stumbled onto two other things that I was unaware before... slightly off topic, but maybe someone can give a quick answer

* Dummy plugs for GPUs if no display is installed: still needed, or solved with newer AMD Catalyst drivers?  (Win/Linux)
(if required, what is there proper name to look in electronics shop)

No longer an issue, no dummy plugs required

* RAM requirement for Litecoin: Does scrypt mining require a certain amount of RAM? (or was that due to bugs in the miner software?) how much?
* if RAM is required, does Speed/CL-timings make a difference?

CGminer uses about 100MB of RAM. I have 6card rigs with 4GB of RAM and they work just fine.




(PS: Sempron 145 with possible/probable option to unlock 2nd core sounds good; any reasons not to go with ASROCK 970 extreme 4?)

Nothing wrong with that board if the PCI-e slots suit your needs.

[Prelude]

Whatever is cheaper. Again, CPU makes zero difference to GPU mining.

CPU is still good to mine those CPU and not so GPU efficient coins like primecoin....

Eh, cheap CPUs like that won't really get anywhere anymore. Mining with the CPU will just drag the GPUs down IMO.

[ivanlabrie]

Mining with the cpu is fine as long as you leave a core free for cgminer.

I mine with 7 threads off my i7 3820 at 4.4ghz and leave one for cgminer...

And btw, r9 290x results are out there: I've seen 880kh/s at 276w and 890-1050kh/s undervolted with intensity 20 and two threads. No hw, and good perf all around.
I think the r9 290 non x will be the winner.

http://www.overclock.net/t/1437876/290x-mining-performance

[carly200]

also speculating on a 290 (no x), but until it is availabe and more results are around, I will wait, or go fot the 7950s
Though too many of them are voltage locked.

What is the way to go for bet Hash/Watt? Lower orignal clockspeed? Lower original Voltage? Any recommendation (with exact hard info)?


if I get the sempron 145, there is "other" core left ;-)
but does CPU mining make sense khas/watt-wise? If so, then maybe a slightly stronger CPU would do the trick.


Anybody have used Low Voltage RAM? pricewise they are the ~same as regular RAM

[ivanlabrie]

Low voltage ram is a gimmick...maybe for a server rig with a gazillion sticks it'll make a difference.
If you can find Samsung 1.35v sticks get them though, they are nice and cheap.

As for the gpus, undervolt to 1.1v and oc ram and core slightly. You have to find the sweetspot and the correct settings.
Refer to this guide: https://bitcointalk.org/index.php?topic=117221.0

cpu mining, yeah, it makes a half decent income...I cpu mine with my i7 3820. Using a lesser cpu makes no sense. Maybe an fx8320.

[carly200]

well, low voltage and regular voltage are about same price, so I might try the low voltage RAM;
is it more likeley to run into problems with that?


CPUs are slow compared to GPUs, but what ist the Hash/Watt (compared to a regular/optimzed 7950 setup)? any numbers?

[carly200]

new questions:

going for a 7950
right now the PC AX7950 3GBD5-2DHPP is a cheap deal. Does anyone know if that one is voltage unlocked? (for undervolting?)

in general, do the "standard" versions or the boost versions get better hash/watt? what type should I get?

[ivanlabrie]

new questions:

going for a 7950
right now the PC AX7950 3GBD5-2DHPP is a cheap deal. Does anyone know if that one is voltage unlocked? (for undervolting?)

in general, do the "standard" versions or the boost versions get better hash/watt? what type should I get?

I'd reccomend dual x r9 280x for mining, or the new r9 290 cards.
Boost tends to suck but I know how to configure it now (thanks to a guy from mcxnow).

[carly200]

If somebody can varifiy if the said model is voltage unlocked, I might actually give it a shot. it is a buy right now...

can you elaborate, what "sucks" with the boost cards? which one gets better hash/watt now? boost or non-boost 7950?





in another thread (https://bitcointalk.org/index.php?topic=301641.msg3527036#msg3527036) somebody says that the 7990 (dual GPU?) is the most efficient.
not speaking about price and money efficiency, is it more efficent hash/watt-wise than 7950s?

[ivanlabrie]

If somebody can varifiy if the said model is voltage unlocked, I might actually give it a shot. it is a buy right now...

can you elaborate, what "sucks" with the boost cards? which one gets better hash/watt now? boost or non-boost 7950?





in another thread (https://bitcointalk.org/index.php?topic=301641.msg3527036#msg3527036) somebody says that the 7990 (dual GPU?) is the most efficient.
not speaking about price and money efficiency, is it more efficent hash/watt-wise than 7950s?

From what I gather the R9 290 is more efficient, for a 270w power draw it pulls 880-1000kh/s.
Boost bioses used to make reaching high hash rate on 7970s a pain, but I think you can reliably get 700kh/s+ (up to 760) on 280X cards like the Dual X now. At least I now know how to configure them for that hash.

[carly200]

my preference is the 290 (non-x) as well, since some report 880 hasrates with good hash/power ration, also gives a good hash-density at the machine.
but since i don't like the reference layout/blower, I will go for a 280x right now. technology has been around, so I expect them to be more reliable for now. (also good deals available)

ordered a sapphire 280x dual-x to see if it is voltage unlocked (40G full retail model, since it was cheaper than the lite retail).
will put it on an old amd64 board to see/check and wait until other components arrive.

for testing i want to go with windows first, should i go with win7 /8 /8.1 or doesn't that matter?

recommendations of drivers/software and versions? installation order?

thanks for any advice, will keep you updated...

[ivanlabrie]

my preference is the 290 (non-x) as well, since some report 880 hasrates with good hash/power ration, also gives a good hash-density at the machine.
but since i don't like the reference layout/blower, I will go for a 280x right now. technology has been around, so I expect them to be more reliable for now. (also good deals available)

ordered a sapphire 280x dual-x to see if it is voltage unlocked (40G full retail model, since it was cheaper than the lite retail).
will put it on an old amd64 board to see/check and wait until other components arrive.

for testing i want to go with windows first, should i go with win7 /8 /8.1 or doesn't that matter?

recommendations of drivers/software and versions? installation order?

thanks for any advice, will keep you updated...

dual 280X is nice...win 7 64 bit, driver: 12.8 for optimal hash rate.
Settings see consolidated litecoin mining guide here.

[MisO69]

I read somewhere that Windows 7 has trouble seeing more than 3 video cards. Is this still a problem? Was it ever?

I also want to build something to mine scrypt coins. Right now I have some USB asics and a few computers doing some CPU mining. If you were going to build a rig, lets say with 6 video cards R9 280x. Which motherboard would you choose? Has anyone tried that new asrock?

[ivanlabrie]

I read somewhere that Windows 7 has trouble seeing more than 3 video cards. Is this still a problem? Was it ever?

I also want to build something to mine scrypt coins. Right now I have some USB asics and a few computers doing some CPU mining. If you were going to build a rig, lets say with 6 video cards R9 280x. Which motherboard would you choose? Has anyone tried that new asrock?

Any motherboard should do, as long as you use powered pci-e risers and good cooling.

And yeah, win 7 doesn't take more than 4 gpus normally, but I think there's a workaround. Linux is better, use litecoin BAMT.

[opticalcarrier]

my preference is the 290 (non-x) as well, since some report 880 hasrates with good hash/power ration, also gives a good hash-density at the machine.
but since i don't like the reference layout/blower, I will go for a 280x right now. technology has been around, so I expect them to be more reliable for now. (also good deals available)

ordered a sapphire 280x dual-x to see if it is voltage unlocked (40G full retail model, since it was cheaper than the lite retail).
will put it on an old amd64 board to see/check and wait until other components arrive.

for testing i want to go with windows first, should i go with win7 /8 /8.1 or doesn't that matter?

recommendations of drivers/software and versions? installation order?

thanks for any advice, will keep you updated...

dual 280X is nice...win 7 64 bit, driver: 12.8 for optimal hash rate.
Settings see consolidated litecoin mining guide here.

Am I missing something on mining profitability with these new ATI 290 non-x cards?  The card itself is $400 and based on the figures of 880khs and 276watts, my ROI on just 1 card all by itself would be nearly 100 days, assuming a static difficulty.  Am I leaving something out of the calculation or are these figueres simply risks you guys are willing to take?

[carly200]

imagine high electricity prices... then your calc is even more off... ;-)

to me it is not about the money (i buy coins for that). but for operation with european electricity prices i need efficiency; not ROI

also, i guess there is a lot more potential in the new cards waiting to be unleashed with improved software...