Ghash/s ?

[NextBigThing987]

super newb here


I understand some of the groundwork of bitcoins and some of the hardware aspects but what are Ghash/s? and what are they dependent on? I assume they depend on the number of computers/rigs or the number/quality of the GPU?

[Bert]

ATI/AMD graphics hardware normally
  - see https://en.bitcoin.it/wiki/Mining_hardware_comparison
Although Mhash/sec is a more commonly used term when talking about single graphics cards or even individual mining rigs.
Ghash/sec is more commonly used when talking about mining pools.
  - see https://en.bitcoin.it/wiki/Comparison_of_mining_pools

[NextBigThing987]

Thanks for the quick response and not being a dick about how I could have found that myself haha


so the higher the mhash/s the better yes?


also why do people say ghash when I see here only mhash? does the g stand for graphics?

[Bert]

Yes the higher the better, normally. But there are other factors. e.g.
   If the initial cost of hardware is 5 times more and the Mhash/sec is only double. It means that your ROI (return on investment) will take longer, but once/if you have gained back your expenses and running costs your profit would be larger.
   Or if the running costs (amount of electricity used AKA Watt/second AKA Joules) is 50% more but the Mhash/sec is only 40% more than a slower card. You would be better off buying two cheaper slower cards then one faster card with higher operating costs.

They are different units of measurement - It saves people from having to type (and read) loads of Zeroes.
1 Ghash/sec is 1000000000 hashes per second
1 Mhash/sec is 1000000  hashes per second
1 Khash/sec is 1000 hashes per second

[NextBigThing987]

you're the man



from what I see 6950s are the most efficient at 75 cents per mhash/s



or even better 2 6770s creating 60 cents a mhash/s

[NextBigThing987]

ok so now I need to know where to get the cheapest 5850 haha. and also if you can have more than one graphics card in one CPU unit.... also can you run the bit coin software multiple times on one CPU/OS if you have multiple GPUs in it?

[Xephan]

ok so now I need to know where to get the cheapest 5850 haha. and also if you can have more than one graphics card in one CPU unit.... also can you run the bit coin software multiple times on one CPU/OS if you have multiple GPUs in it?

If you're using a graphical frontend for mining like guiminer, you just need to run one copy and it will allow you to setup multiple GPU to mine.

[NextBigThing987]

ah so it'll just operate more efficiently through that one program I see.... mixing up the logical order of how the computer works with the application... that makes more sense now




one more quick question that should obviously not be in this thread but o well....


what is the most important hardware spec that will effect a persons bitcoin average per day? mhash/s?

[Xephan]

one more quick question that should obviously not be in this thread but o well....
what is the most important hardware spec that will effect a persons bitcoin average per day? mhash/s?

Yes, in a way MHash/s is the primary factor determining your bitcoin earnings. But at low MHash, it's also highly dependent on luck or variance as they call it. You can smooth out the effect of luck by joining a mining pool.

[hmblm1245]

For noobs pooled mining is the best way to go unless you dive in at more then 3+ ghash. even so i am at 2.5 ghash and still pool mining for the constant btc flow rather then the chance of finding a the block jackpot of 50btcs once every 4 - 6 weeks most likely. 

Mhash/Ghash is the most important hardware measurement to focus on, but with that comes a power supply that can handle the GPUs you choose. Also you will need a mobo that supports a bunch of pcie slots and as of late getting at least a atholon II x4 is becoming the norm. this is all not to mention the wattage used by the system as a whole.