Bitcoin Forum

I was looking at radeon 7950,7970,R9 280X,R9 290 and R9 290X.I saw their performance from this link:

https://litecoin.info/Mining_hardware_comparison

I am wondering can we really get the exact hashing power like its written in the chart for these cards?Also different brands cards generates different amount of hashing power.That's also a problem.I don't understand which one to get.

It depends on the amount of onboard ram, clock speed, and memory speed, which is why different brands may generate different hashing power.  And yes, if you tweak your card just right, you can get whatever's on those comparisons

The numbers on that chart come from people reporting what they got on their system.  Not a 100% guarantee what you will see, but a fairly reliable place to start.  If you want to be conservative in estimates, maybe go 5% under the reporting hash rate to be safe?

6950 Mines ~400-500Kh/s and sell for $80-$100 second hand.

Most likely not even close

I'm getting 550-580 Kh/s on my Vapor-X 7950.  Just ordered 4x R9 280x's for a new rig, hope to get 700+ Kh/s on them like others are here.

I recommend buying a few sapphire vapor-x 7950s. I run three, each one does 645kh/s average  sits around 68c temp and resells for $250

Fairly quiet as well. They are workhorses

I'm using hd 7970 non GHz which is i suppose same as R9 280X and i get about 700-730 khash @ 1038 core 1600 mem

my dual fan Powercolor PCS+ 7950 from newegg.ca arrived last saturday and i paid $214 can with 6% off coupon code..
why on earth would i buy some guys used one for more money ? LOL

edit:
PS: it's quiet :)

Keep in mind that there is new scrypt mining technology on the horizon that will make GPU mining obsolete.

I have that gigabyte oc3gd exact code r9 280x and I am getting 730khash :D

I think he's referring to Alpha Technology's recent announcement regarding their alleged litecoin ASIC. With a sufficient front end you'll be able to mine any scrypt-based coin with this thing. I doesn't matter whether it's a new coin or like litecoin in use for years.

i recently purchased a 7970 for about £203. the hashrate was supossed to be 520kh/s according to the litecoin hardware comparison. but ive managed to tweak it to about 620kh/s while using it for 2 monitors. hoping to reach 700kh/s with no monitor support

Sapphire Vapor-X 7950's are a good investment, I have mine hashing at a stable ~635 KH/s with little noise or heat generated.

Plus the "horizon" is much further than you can piss. you still have a fair crack of the whip for gpu mining yet.

if people were close we would ALL know about it.

I am running max 7950 saph vapor-x and u cant undervolt them im at 5200 hash with 8 of them...thats the max u can do. usually ppl only do 540 hash with them. im going to invest in two more machines in jan i am buying the new r290s doing 1m per card roughly (940-1m)

Buy used GPUs and you'll make your $$ back in half the time. Once a used GPU pays for itself, sell it and buy a new one.. run them too long and they will die/start having problems making the resell value worthless. My favorites in no particular order are 5970s, 6950s, 5850s, 7950s, and 7970s.

2X 7950s getting +/- 1.35Mh/s.

Could push them a bit more (and have done so) if I wanted but prefer longer lifespan to higher hashrate. The max achieved per card is about 720Mh/s but not really sure they work efficiently at that high of speed. Performance/efficiency is just right at 650-680Mh/s. In my humble opinion and in my personal experience, maximum achievable hashrate isn't the only thing to consider in a card.

7950s are good cards, a few months ago they were arguably the best choice to consider for scrypt-mining. Now though, they've jumped up in cost and are becoming more and more difficult to find...the 280 or 280x would probably be a better choice currently....though I don't own one yet so this is speculation. From what I know of them, you basically get a newer/improved 7970 for just a little bit more cost (if any) over a 7950 (feel free to correct this claim if it's inaccurate) and around $100 less than a 7970.

Perhaps. Hell, I don't know...just what I would consider doing if buying another card today. Well...that is, if you can find one.

Don't listen to me though...as stated previously, I don't own an R9 card.

You asked for hashrate of 7950s so I offered my own experience...the rest is only personal opinion based on speculation. Honestly, what's best is to do your own research before making any purchasing decision and don't ever buy anything just because some numskull in a troll-flooded forum told you to.  ;)

its impossible. ill even link my settings if u want

I think i got my 7990 on sale for $600 but it does around 1.333 mh

My setup guide is here:
https://bitcointalk.org/index.php?topic=280725.msg3103652#msg3103652

Good luck finding anything in stock. I had a hell of a time sourcing cards. I had to go to local computer stores and pick up whatever stock they had. Buy the new R9 series cards if you can. As for powered PCIe risers, lol good luck..

Does anyone know where I can buy PCIe risers in bulk from China?