Bitcoin Forum

Hello guys!
I'd like to learn something about bitcoins before i invest more money and i have 2 ways to go:
1) FPGA- it consumes less power but it's not as efective as GPU. I can get 200MH/s @ 10W for ~250$
2) 5870+5850 in Xfire. both cost ~260$

Now i have a few questions on start:
1. Is it good to mine on 5870+5850? AMD site says they can be xfired.
2. On what mobo, cpu, memory, disk etc should i focus? Can it be just a random mobo which handle 2 GPU?
3. Can FPGA/GPU run 24/7 or do i have to do a breaks like 30mins every 24 hours or something?
4. How to minimalize power consumption? I pay ~0,18$ per kWh

Thank you for help :)


PS
I've read so many articles and topics about it so please dont paste links like https://en.bitcoin.it/wiki/Mining_hardware_comparison :D

I would say it's a bit too late to mine for bitcoins now using consumer desktop GPUs. ASIC is the way to go, but it's very difficult to land one even if you are willing to pay top bucks.

I would treat bitcoin as a stock or commodity now, and just trade it.

Litecoin, on the other hand, is still a fair gain for home miners.

agreed you are atleast 6 months too late to the game, GPU's are probly going to consume more hydro than what you will make mining bitcoin but litecoin is a good alternative for GPU farms. as for FPGA they will work but you should really be looking at investing into ASIC hardware, they are going for as little as 150$ for 4.5 Gigahash at BFL.

I have been mining with two 7970's a 6950 a 5870 and a 5850 as well as two FPGA units, i would know. The time of ASIC is upon us, the network is growing at an incredible rate wich makes GPU mining worse and worse by the day.

Which GPU is good for litecoin? Anyone tried the latest AMD SkyServer 10000 GPU?

I meant litecoin is still a fair game, in my previous post.



I would say Radeon HD 7970 should be a good start. You get the money back in about three month, or sooner, if the trend is still on.

ASIC from BFL are probably a scam so it's waste of money and time. I'm thinking about GPUs becouse they are easy sell if price drop to no profit level. Could someone answer my questions? :)

The best dollar/hash ratio seems to be the Radeon 5850/5830 GPU's. They are capable of 300-350+ Mh/s and can be found on Ebay for around a hundred bucks each. By my calculations, two of them should net about .05 BTC per day - about $5 per day at the current exchange rate.

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

Two 5850's are around 300 watts. That's 7.2 KWh per day. At 18 cents per KWh, that's an energy cost of about $1.30 per day.  $3.70 per day net will pay off $200 cost in under two months - assuming a relatively stable exchange rate, of course - and there's the rub! The exchange rate could go much higher, or it could drop back down. That anybody's guess. You also have to factor in the difficulty rate. As network hash rate rises, your return drops. A lot of folks keep saying all these ASICs are going to come on line, but I have my doubts that its going to happen quickly. The BFL ASIC seems to be classic vaporware with no materialization in sight, and some people saying its an outright scam. If it is, its a very elaborate 'long con' type of scam. Only time will tell. The Avalon ASICs are coming out, but in pretty low numbers. IMO not enough to seriously effect the hash rate for some time (years end maybe).

1. crossfire function is irrelevant. The mining software does not use them that way. It will see each card individually.
2. Nothing special. Just get a MoBo with two x16 slots - more if you want to use more GPU's later. CPU doesn't matter, and a GB of budget RAM should be fine. Hard drive really isn't even needed, it can be run from a flash drive.
3 24/7 shouldn't be a problem
4. Don't go nuts with a huge power 1200W supply (a good 430W will do), don't add a lot of unnecessary components, drives, etc. Just keep it simple. Don't even need a monitor, actually, just log-in to it remotely.

Thanks this is good info :)

What should i choose 5870+5850 for 260$ without warranty or 7970 for 450$ with 24 months warranty? Do GPUs burn very often when they are mining?

Only if you go crazy with the overclock.