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Hey guys, I've got a Radeon 4870 that does 89Mh/s. Pretty bad considering it's not modest on sucking juice.

What do you guys advise I upgrade to? Preferably under 100$, since I'm a college student. I was thinking a used 5770.

Aloha,
-Free

https://en.bitcoin.it/wiki/Mining_hardware_comparison

Select here and search something good on ebay...

I don't wanna spoil all the fun guys, but this belongs in mining.

I got a Radeon HD 5970 on Craigslist for 400 USD, which is about half what it sells for new. If everything goes well I should have paid for it and all the electricity in a couple of months. If everything doesn't go well, I guess I'll have to console myself with my super-cheap video card.

I wouldn't buy new hardware solely for mining unless I could get an equally good deal again. Look on Craigslist or sites like that. A used 5770 sounds reasonable and will be a nice upgrade for your PC too.

Given your constraints, a 5770 would indeed be the best choice.  I've seen them new for $99 after rebate recently.

I shall check Craigslist, but being that I live on Kauai (Small island on the west of the Hawaiian chain) I don't know how much tech will be there. ;P

I do a lot of GPU calculations, and have been getting into parallel programming recently. So this wouldn't only be for mining purposes. I'm more interested in porting CAL++ to poclbm.

I too was looking for something under 100, and I too decided on the 5770. However, after looking around Ebay for a while, I figured I may be able to get lucky going a step or two up. I ended up spending 110 (including shipping) on a 5830. So look around.

My two 5970's in a pay-per-share pool (As in I get paid for every share I submit, not every time the pool solves a block) will earn me enough profit (So after electricity) in less than 30 weeks. With the three cards, this time then drops even lower, to around 25 (Rough guess). So every 5 - 7 months I can buy a new 5970 (If I wanted) to add to the mining rig(s).

With that much power, why not go with a score based pool so that you can save 8% in fees?

The best price/power card will be probably 6970, because it has almost exactly the same power while being at least 40% cheaper (last time i checked).

However that does not necessarily apply to the best Watt to Mh/s ratio.

My 5830 was $110 after rebate and gets me 270Mhash/sec. I'd say it's up there.

I also just picked up a 5770 used off Kijiji (think Craigslist for canada) for $80 cash, and it gets me 180Mhas/sec.

I'd say both would be contenders!

Are you comparing a 5970 to a 6970? Because the 5970 will absolutely crush the 6970.

Hold on, I'm gonna draw up a graph for mH/s per watt per dollar. :P
Lemme figure this out. So I can figure out the cheapest, most efficient card. Assuming of course that 2 cards scale evenly to 2x... Perhaps I'll check with like 1.9x too.

Hey Guys!  I've known about BitCoins for a while now (and I LOVE the idea), but tonight I discovered this whole GPU mining world. I am interested in buying a machine and getting started.  I would be willing to put about $800ish in a machine.

I'm looking to get the biggest bang for my buck.  I don't know what that is, so here I am, reading up. :)

I was wondering, wouldn't it be best to buy two 5870 @ 340 Mhash/s @ $200 instead of one 5970 @ 600 Mhash/s @ $500?  Why are so many people recommending the 5970's over the 5870's?

What would be the best cost-to-Mh/s ratio overall without freeqaz $100 limit?

Thanks, and you'll be seeing more of me!

 
 I just picked up 2 Used HD 5850's from Ebay for ~$170 each. A slight savings over new one's w/ rebate at Newegg (but no rebate to deal with). I upgraded the BIOS's to the ATI 5870 bios and currently running at 900/900 Core/Mem Clocks. I don't know what their power draw is but I'm getting ~316Mh/s each. That's around the bottom end of an unoptimized 5870 according to the Mining Hardware List.

I'm currently writing a Java app in Swing that will allow you to input the cost of a card, the megahashes per second, and the wattage, then give you some sliders to pick what means the most to you. For example, if you value efficiency and performance, but not so much price, then it will let you get the value for that. I've got a basic algorithm so far.

(((mHs/power)*x) + ((mHs/cost)*y))/((1mill.mH/mHs)*z)

Where x, y, z are the sliders to account for preference. I've gotta test this out some more, but so far it's been doing alright.

I had a 4870 running at 90 MH/s and wanted to get something better without spending a small fortune. I reckon that the 5850 and 5870 are the best bang for your buck at the moment. In the UK I picked up a new 5870 for £130 + tax & P&P. It's now over clocked (but not optimized yet) and kicking out 320 MH/s. Second hand 5870s on Ebay were going for more than I paid for a new one, so don't assume 2nd hand is cheaper...

It's worth noting that the 5850 uses about the same power as a 4870 and the 5870 uses approx 10% more.

SUPER NITPICK: I'm mildly irked by the popularity of quoting efficiency in "megahashes per second per watt" when folks could use "megahashes per watt-second" or "megahashes per joule" or even the far more immediately usable "terahashes per kWh".

I have 6970 and power consumption/MHs is 300W/320MHs for whole PC.
Other components: Intel C2D@3200MHz,4GB DDR3,1xSSD,1xHDD,1xDVD,some USB devices, Power Supply Enermax Modu 82+ II 525W.

started work on the calc program. Gotta finish out the GUI (haven't worked much with Swing) but then it should be good to go. I'll distribute the source with it so that others can expand upon it.

http://freeqaz.com/bitcoin/bccalc.png

Can't wait to see the result  :)
Keep up with the good work !

 If I could go back in time and do it again, I wouldn't have bought a card for mining... I would have just bought bitcoins directly. I could have made something like a $500 profit already, where right now I'm still about $200 in the hole.