Buying a 7850 for $140 for mining - worth it?

[guitarplinker]

Hi, I currently have a mining rig with an ASUS 7850 2GB doing about 400KH/s in LTC mining. I've found someone willing to sell their exact same card for $150 locally, and I'm hoping to get the price down to $140. The card is basically brand new, it's been mined on for a week, but he says he can't figure out the right configs/OCes to make it worth mining with. I recently figured out how to get mine to do 400KH/s overclocked, or 300KH/s on stock.

So what do you think, would it be worth it to buy it and mine with it? I know it's a very good price for a brand new basically ASUS 7850 2 GB, and I can always crossfire them in games too if I feel like playing ever (even though Xfire isn't really working correctly ATM)

I also figure that I can mine with it for a few months over the summer and then sell it before the 8xxx series releases in September - hopefully make some money as well as sell the card for a fair price.

What do you guys think about all of this? Would you take the plunge?

[spider4]

If you get warranty with the card take it, make some money with it and sell it if you want 

Can you share your clock and miner settings if it isn't a secret?

[jamesc760]

every card is different, in terms of hashing power. Your current Asus 7850 can do 400 Kh/s but the new Asus 7850 may not do 400 Kh/s, no matter what your settings are.

$140 for a 7850 is a decent price for a used card. I bought a Sapphire 6950 for $100 off Craigslist and it's mining at 400 Mh/s. A good 7850 will do around 300 Mh/s BTC or 300 Kh/s for LTC. A 7850 will consume about 130 W, compared to a 6950 at 200 W.

[zvs]

I think the cheapest I've seen a 7850 including the rebate is $132 on Newegg.... after selling games, that would have been about $110 at the time (5-24, tomb raider + bioshock were worth more then, etc)..

They're regularly up there for $140, including rebate... and the games.

Though some are better than others (re: 2GB vs 1GB, etc).  I think the cheapest I've seen a 2GB is $160.  I bought an MSI Twin Frozr 2GB for $170, after rebate, on May 12th... back then it was worth it to take it out of the box and mine with it.

I don't think so now.  If you're going for pure profit... you'd just buy it, do the rebate, sell the games, then sell the card as 'new in box'.  

I think the 7790's on newegg are a better deal, though.  I wish I had bought more a few months ago...  they use like 70 watts for 300-320mhash and you could get them for about $75 after selling the games..

(re: i got about $80 each for my sapphire 5830's on amazon after fees, was replacing those cards with 7xxx series)

[guitarplinker]

If you get warranty with the card take it, make some money with it and sell it if you want 

Can you share your clock and miner settings if it isn't a secret?

Sure, here are my settings for 400KH/s:

Batch file to start CGMiner:

Code:

setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer.exe --scrypt -o stratum+tcp://multipool.in:3334 -u lolnope.jpg -p lolnope.jpg --intensity 17 -g 1 --thread-concurrency 8192 -w 384 --lookup-gap 2

And for the overclock:
Core clock: 1150 MHz
Memory Clock: 1650 MHz
Voltage: 1.225V

I wouldn't feel safe running those volts 24/7 but with that it does hit 400KH/s.

[Galimore]

every card is different, in terms of hashing power. Your current Asus 7850 can do 400 Kh/s but the new Asus 7850 may not do 400 Kh/s, no matter what your settings are.

$140 for a 7850 is a decent price for a used card. I bought a Sapphire 6950 for $100 off Craigslist and it's mining at 400 Mh/s. A good 7850 will do around 300 Mh/s BTC or 300 Kh/s for LTC. A 7850 will consume about 130 W, compared to a 6950 at 200 W.

You can actually get them cheaper than that new. I got 8 Sapphire 7850's from newegg for $150 each and sold the never settle codes for almost $30 a pop on ebay. They're all getting ~370kh/s and run very very cool at 75% fan (even with a large overclock). Not to mention the power draw is very low, I've been running 4 each on two 850w power supplies for months without any issues.

Edit: Looks like the Never Settle deal is over. Sucks, it was basically $30-$40 off any new AMD card.

[TheSpiral]

If you get warranty with the card take it, make some money with it and sell it if you want 

Can you share your clock and miner settings if it isn't a secret?

Sure, here are my settings for 400KH/s:

Batch file to start CGMiner:

Code:

setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer.exe --scrypt -o stratum+tcp://multipool.in:3334 -u lolnope.jpg -p lolnope.jpg --intensity 17 -g 1 --thread-concurrency 8192 -w 384 --lookup-gap 2

And for the overclock:
Core clock: 1150 MHz
Memory Clock: 1650 MHz
Voltage: 1.225V

I wouldn't feel safe running those volts 24/7 but with that it does hit 400KH/s.

That's basically the same setup I have for my 7850's, just with lower memclocks and voltage (crappy power supply).
They're good deals, dollar per hash, compared to a lot of other cards, especially in the 7xxx series. Hashes per watt is in favor of 7950, 7970, 7990.
As for 7790's, terrible for LTC mining, great for SHA256 going by watt/price per hash.

[zxc003]

Sure, here are my settings for 400KH/s:

Batch file to start CGMiner:

Code:

setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer.exe --scrypt -o stratum+tcp://multipool.in:3334 -u lolnope.jpg -p lolnope.jpg --intensity 17 -g 1 --thread-concurrency 8192 -w 384 --lookup-gap 2

And for the overclock:
Core clock: 1150 MHz
Memory Clock: 1650 MHz
Voltage: 1.225V

I wouldn't feel safe running those volts 24/7 but with that it does hit 400KH/s.

3x Sapphire 7850 1GB at 1160/1125 1.145V and this settings:

Code:

 --worksize 256 --lookup-gap 2 --thread-concurrency 4800 -g 2 --intensity 12

The result is ~1220 kH/s overall for scrypt currency.

[MangoJ]

According to https://en.bitcoin.it/wiki/Mining_hardware_comparison
a 7850 will do about 300 normally.

I am letting go of some 5870s and 5970s that pull 450 OC'ed or 420 normally.
If interested hit me up.