Litecoin build for noobs: 3x 7950s (1.8 MH/s) in a $10 crate case

[itcamefrommars]

okokok... On Sunday amazon had quite a few of the twin frozr III's and I bought 2 (should have done all 3 for this rig).
Taco - Awesome write up - but I have to wonder if this post helped caused the shortage of these cards and drove the price up on ebay to over 900$ lol

those reaper settings are spot on btw.. I'm pulling a little over 600kh a card running them stock in a dual card rig.  Def a good recommendation on them.  Thanks!  Amazing gpus
I'll tip you some of their mined LTC


I'm going to try out the 7970's from this line on another rig I think.  Have you used those?

[Starlightbreaker]

Hey, trying to stay out of here for a bit, but someone brought these cards to my attention and I thought you guys might want to know about them if you're still building rigs

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202030
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202031

They are AMD 7970 reference boards and thus have really solid voltage regulation and RAM, VRMs are all really well cooled.  As such they should all also have voltage control.  Once these go out of stock they will likely not be replaced, so grab them while they're still around.

edit: voltage control confirmed with sapphire trixx http://www.overclock.net/t/1378557/sapphire-100352-4l-and-21196-00-20ghd-7950-the-final-holy-grail-of-hd7950s

got my 7950-4l today.

i can drop the voltage.

also, as with my other HIS 7950s which was locked.
apparently flashing 7970's bios works wonder.

[Joerii]

Hey, trying to stay out of here for a bit, but someone brought these cards to my attention and I thought you guys might want to know about them if you're still building rigs

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202030
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202031

They are AMD 7970 reference boards and thus have really solid voltage regulation and RAM, VRMs are all really well cooled.  As such they should all also have voltage control.  Once these go out of stock they will likely not be replaced, so grab them while they're still around.

edit: voltage control confirmed with sapphire trixx http://www.overclock.net/t/1378557/sapphire-100352-4l-and-21196-00-20ghd-7950-the-final-holy-grail-of-hd7950s

The BIG problem with trix is that it doesn't save the power settings when you restart your system. That means you can't autorestart the system once in a while without babysitting it.

Also.... why are you tryingto stay out here ? I really enjoy your posts. Please, also give us an update about your VERY interesting MC2 concept !

[tacotime]

Also.... why are you tryingto stay out here ? I really enjoy your posts. Please, also give us an update about your VERY interesting MC2 concept !

I will lose my job (and $25,000 for the remainder of the year) if I don't pass my exams that are coming up this week and the following week, so I need to complete them first

MC2 update coming soon, tons of things will be changed (new PoS strategy, more optimized hashing algorithm) based on the feedback I have received.

[Simran]

Umm I have 3x 7950 and 1x 6950 on this rig.. When I use cgminer, it gives me the error: "Error -5: Enqueueing kernel onto command queue. (clEnqueu
eNDRangeKernel)" on 3 out of the 4 cards. This usually happened to me when I didn't export the variables needed by cgminer, but nothing yet. I have 10 GB RAM on this, do I need more?

[Trommie]

How much does the build quality vary on 7950s? Wondering whether I should get an XFX HD7950 or get more of the Saphire 7950 (The Saphire costs about £50 more, that about $75).

[bitly]

I'd also like to use the rig for some computing. Thinking of getting an i7-3970k with 64GB of RAM. Should I get a bigger power supply for them?

[atrane21]

Hey, trying to stay out of here for a bit, but someone brought these cards to my attention and I thought you guys might want to know about them if you're still building rigs

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202030
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202031

They are AMD 7970 reference boards and thus have really solid voltage regulation and RAM, VRMs are all really well cooled.  As such they should all also have voltage control.  Once these go out of stock they will likely not be replaced, so grab them while they're still around.

edit: voltage control confirmed with sapphire trixx http://www.overclock.net/t/1378557/sapphire-100352-4l-and-21196-00-20ghd-7950-the-final-holy-grail-of-hd7950s

ok so i picked up 3 of the 7950 4L models for my 2nd rig. I can't get these suckers to go past ~530kh/s i've tried a ton of different settings and configurations with no go. Anyone have any luck getting 600kh/s+ on these??

[AmDD]

Hey, trying to stay out of here for a bit, but someone brought these cards to my attention and I thought you guys might want to know about them if you're still building rigs

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202030
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202031

They are AMD 7970 reference boards and thus have really solid voltage regulation and RAM, VRMs are all really well cooled.  As such they should all also have voltage control.  Once these go out of stock they will likely not be replaced, so grab them while they're still around.

edit: voltage control confirmed with sapphire trixx http://www.overclock.net/t/1378557/sapphire-100352-4l-and-21196-00-20ghd-7950-the-final-holy-grail-of-hd7950s

ok so i picked up 3 of the 7950 4L models for my 2nd rig. I can't get these suckers to go past ~530kh/s i've tried a ton of different settings and configurations with no go. Anyone have any luck getting 600kh/s+ on these??

Per my post earlier. I have these same cards and can get a max of 530kh/s. If you find any settings that can get you up to 600, let me know!!! 

[atrane21]

Hey, trying to stay out of here for a bit, but someone brought these cards to my attention and I thought you guys might want to know about them if you're still building rigs

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202030
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202031

They are AMD 7970 reference boards and thus have really solid voltage regulation and RAM, VRMs are all really well cooled.  As such they should all also have voltage control.  Once these go out of stock they will likely not be replaced, so grab them while they're still around.

edit: voltage control confirmed with sapphire trixx http://www.overclock.net/t/1378557/sapphire-100352-4l-and-21196-00-20ghd-7950-the-final-holy-grail-of-hd7950s

ok so i picked up 3 of the 7950 4L models for my 2nd rig. I can't get these suckers to go past ~530kh/s i've tried a ton of different settings and configurations with no go. Anyone have any luck getting 600kh/s+ on these??

Per my post earlier. I have these same cards and can get a max of 530kh/s. If you find any settings that can get you up to 600, let me know!!! 

Yea i'm kinda pissed. i was expecting to get AT LEAST 600 out of these

[Vigil]

I have two 7950s and I am able to get between 550-600 kH/s using GuiMiner-scrypt's default 7950 settings. Usually, it is around 560 kH/s. Once it was running stable at 605 kH/s but that was the first time I used it and haven't seen that consistently since, even though I think I am using the same settings.

You have to imagine that many of these stories about higher than normal hash rates are just that - that is how message boards are, there are always those Keyboard commandos that can do the most amazing feats. 

[tacotime]

You have to imagine that many of these stories about higher than normal hash rates are just that - that is how message boards are, there are always those Keyboard commandos that can do the most amazing feats.  

Balthazar:


Me:



Posted my reaper kernel here: https://bitcointalk.org/index.php?topic=117221.msg1834570#msg1834570

[Vigil]

Attempted to use your settings but Reaper won't connect to my pool.

[tacotime]

If it's stratum you must use the mining proxy (see sig threads)

[atrane21]

You have to imagine that many of these stories about higher than normal hash rates are just that - that is how message boards are, there are always those Keyboard commandos that can do the most amazing feats.  

Balthazar:
http://anonymouse.org/cgi-bin/anon-www.cgi/http://img38.imageshack.us/img38/2250/reaperg.jpg

Me:
http://i45.tinypic.com/dpeil3.png
https://i.imgur.com/HDeK0eC.png

Posted my reaper kernel here: https://bitcointalk.org/index.php?topic=117221.msg1834570#msg1834570

what brand and model card are you using?? I've tried a ton of combinations and i seem to get best khs from stock clocks. I'm using the sapphire 4L

[tacotime]

both XFX and gigabyte cards, brand doesn't seem to make any difference as both hash at exactly same rate

[AmDD]

I did have slightly better luck with reaper vs cgminer, however I could not figure out how to setup a backup pool with reaper. That alone is worth the few kh/s loss in switching to cgminer.

[Vigil]

If it's stratum you must use the mining proxy (see sig threads)

Thanks, I missed that.

[jhd]

very beautiful mod. Love 7950 :-)

[Vigil]

After trying the mining proxy, my display GPU which isn't even being used to mine crashed completely. I reset and now none of my miners work. Not Guiminer-scrypt (CG), reaper, Guiminer, etc. And the display gpu crashes constantly.