Bitcoin Forum

Hi there,

I am still thinking about switching from BTC to LTC mining and was wondering why most people mine LTC with 7950 instead of 7970. Any good reason for that?

I wondered the same. My rigs are built with 7970's --> maximum hashing power per motherboard. All hitting 750kh/s and some even 790.

So yeah..

Because your cost calculations weighted with equipment costs and wattage results in a better earning and shorter ROI on 7950s

It's because people with 7950s aren't mentally challenged. 7950 hits 690Kh/s easily with way less power usage and a lot less cost per GPU.

The reason why 7950s are generally preferred to 7970s is because of their superior price/performance ratio. 7950s are also often considered to be more efficient than 7970s (i.e. more Kh/s per watt) although in my own experience I find them to be equally efficient when used with the proper settings.

But I'd say if you already own 7970s, there is really no reason to go out and buy yourself 7950s to replace.
You can still configure 7970s to perform arguably equally efficient as 7950.

I'd like some numbers on that better kh/J claim. Shorter ROI doesn't mean shit if you're planning to mine in the long run.

Enjoy spending an extra $100 per GPU and extra money for electricity costs to get almost no increase in hash rate (if you can even get 700Kh/s, that is).

I'll mine with my 4 GPUs doing 700Kh/s each while you mine with your equally expensive 3 GPUs doing 750Kh/s each.

Enjoy trying to sell your 7950s when I dump my 7970s at the end of the road..  ;)

Thanks, I'll sell them for the same price you sell yours.

Because an extra $100 per video card isn't worth an extra 100-150kh/s.

I still haven't found the settings to break 600kh/s each but I'm still happy with the results and happy that I didn't go with the 7970s.

I think people who buy 7970s are just bad at math or wanted a nice gaming card that they can mine with on the side.

And what are these settings for getting 700kh/s from an 7950? And what 7950 model?

That information has been available for a long time now. I've been talking about it for nearly two months in #litecoin and it's been posted on the Litecoin forums for a few weeks.

I did the ROI on all the 5000 6000 and 7000 series.  The result was that the 7950s outperform the better cards based on dollar value.  There is usually a market up by hardware manufactured for the best of breed models to offset that fewer people will choose them over cheaper cards.  There are a few best of breed 6900s and 5900s that do very well at hashing rates per dollar but fail to provide a cost benefit to 7950's lower wattage

As to the resale value.  I'm writing off depreciation of hardware assets so it somewhat offsets the loss when these cards go back on the market in about 18 months.  Factoring depreciation (not expected resale value) 7950s still do better.

I keep up on the price changes and if and when 7970s break into the sweet spot of the cost value curve I'll start buying them.  Until then 7950s all the way.

I get ~550kh/s with my 7950's (Sapphire 40g)

Based on the price of cards and power consumption of the 7970's as well as current coin prices the extra $100 isn't worth it.

7950's can get 660 KH/s without breaking a sweat. 7970's are pickier to tweak. Price.

interesting thread...
i did some math here in Romania:

7950      1300 RON (394$)      Avg 600KH   2.16RON/H (0.65$/H)
7970      1650 RON (500$)      Avg 800KH   2.06RON/H (0.62$/H)
7970      1700 RON (515$)      Avg 800KH   2.12RON/H (0.64$/H)

7950      1300 RON (394$)      Avg 620KH   2.09RON/H (0.63$/H)
7970      1650 RON (500$)      Avg 760KH   2.17RON/H (0.65$/H)
7970      1700 RON (515$)      Avg 760KH   2.23RON/H (0.67$/H)

So basically there is no tangible difference between the 2.. Maybe 7970 will have a better resale value when you sell your farm.

Unless of course i`m wrong about the averages. Because i saw 7950's that do 640KH but i don't remember many 7970's doing 800.. So basically if the math is done with an average of 620 for 7950 and 760 for 7970 you actually get a better deal getting 7950's

Could you please link the thread.

How about I just tell you the settings for the correct card: http://fuxx.us/mining-hardware-comparison

repost them plz

are you bli
are you blind/ just follow the link

As long as the kh/J rating is the same, there are no 'extra electricity costs', relatively this stays the same but yet you reap better benefits from lower difficulties, because you have more hashing power.

You make loose claims and sound butthurt that you don't have 7970's somehow. The cards don't instantly lose their value either, so all bullshit about ROI is mere speculation as well.

Says the lard that can't into math and thought he was being super 1337 by buying 7970s.

Great informational retort.

If you had done your math properly, you'd have taken into account that the cards dont *POOF* lose all their value when you buy them. You don't 'lose' an extra 100$ which has to be completely paid back by the cards.

Also I had 4x the ROI of my rigs by lucking out on FTC - and that ROI was before I even bought them! What I'm saying is ROI is mere speculation. There is no 'math' in speculation. It's just philosophy with numbers. You can't predict the market.

i can't find them(not the link, but the thread about the settings)

You bought three cards. I bought four. The total cost was the same. Four gets more coins. Who gets more money back?

Buy 7950s for mining. I have 2x7970 and 4x7950, and I can say the 7950's have the same performance at a much lower energy cost. The 7950's can also seem to handle a lower voltage a lot better than the 7970's. If the rig is going to be used just for mining, there is absolutely no reason to buy 7970s, as there is no benefit to them when it comes to how much money you're going to make.

From this table I can See the Gigabyte HD 7950, GV-R795UD-3GD doing 300 Mh/s and on other configs up to 692 Mh/s.

I really like Gigabyte so I might buy a 7950 model to try out.

So has anyone already tried the Gigabyte Radeon HD 7950 GV-R795WF3-3GD?
And if yes, what is the difference between the normal and the OC Edition?

All my cards (13) are 7970s. 9 out of 13 can hit 800KH/s, and 4 of those can hit 825kh/s. I run them all at 725KH/s, though, which gives me the best kh/s/w ratio at about 3.4kh/s/w.

My Sapphire 7850 is giving 402 Kh/s. I definitely prefer 4x7850 over 2x7950. Price is almost the same, but performance is better. With 7970 you overpay even more... But if you short on place and do not care much about saving money - then go for it!

Thanks for pointing that out. Wiki is updated with the correct model. This answers your question.

Thanks!

But the question about the normal and the OC Edition remains. Any benchmarks/experience on those two different versions?

I didn't know there was an OC edition. This is the only one I know of: http://www.newegg.ca/Product/Product.aspx?Item=N82E16814125414

Page is in German, but card name is equal in all languages:
http://www.gamersware.de/product_info.php/info/p21173_Gigabyte-RADEON-HD-7950-OC--Windforce-3X--3072-MB-DDR5--Mini-DP.html&ref=35

Actually I bought 12 but w/e

They don't list a model number. I'd have to assume the OC is the WF3.

You can't count on getting 800KH out of all 7970s... I have only seen a few people do it. Plus 7950's use 50w less power.

You can actually, if you have the right series. Just make sure any subsequent cards are the exact same ones, preferably from the same vendor.

All my sapphires (11197-03-40G) ALL do 750 @ exactly the same settings, and some golden samples do a little more. But baseline, they all hit 750.

Yes it does, it means your getting more coin per day.... long term, that bit more coin you say doesnt mean shit could be a fortune.

Lol no you get more coins a day if you have more hashing power. It's all about the kh/J. Energy is a daily spending. Coins are a daily income. The actual hardware is a one time purchase.

This

I have a 7970 (msi lightning) , one of the best 7970's you can get and there's bugger all i can do to get it over 650.

My 7950's do 670-680 easy, and that's not even pushing them (I can get over 700 but choose not to due to extra heat/power).

How many MH/s are 7950s getting on SHA-256? Seems the highest I've seen is about 550MH/s, while 7970 do 700MH/s easy enough.

605Mh/s is easy enough. SHA coins are shit, though.

2 of my 13 cards are Lightnings also, they are the worst of the bunch unfortunately. Took everything to get 700KH/s out of them.

Too get at least 600, you need to powertune to 20.

Wrong.

Sounds like you took the worst 7970 out there. As I said, I've got a batch of 12 Sapphire 7970's that ALL do 750 easily, most of them more.

Can some of you guys post your CGMiner settings for your 7950's? I have an xfx 7950 DD, and I can't get it past 500 KH/s...If I try to OC at all, the driver crashes >:(

Also, any thoughts on this card for mining?

Powercolor Radeon HD 7970 925MHZ 3GB 5.5GBPS GDDR5 V3 DVI HDMI 2XMINIDP PCI-E Video Card 
 
It's on sale at NCIX for $359.99.
I'm looking to add a card, and I'm torn between the 7970 and another 7950

What settings do you use for 750s?  And 800?  :)  Right now I'm getting 730s with 1050/1500 on my Sapphire 7970s

i find the power to hash ratio is higher with a 7950.

But it also has less resale value. You're right about cost per watt and heat, 7970 was running way too hot when I got it and I have to undervolt it.

O really? so the % of original price on resale is higher for the 7970?

Anyone?

Anyone?

So... did we come to the conclusion that 7950's are better now?

If so, what exact model gives you the most kh/s?