# 5.2 Mining Hardware
###### tags: `Blockchain`
The following notes are taken from [Coursera](https://www.coursera.org/learn/cryptocurrency/home/week/2)
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### SHA-256
- General purpose hash function
- Part of SHA-2 family: SHA-224, SHA-384, SHA-512
- Published in 2001, designed by the NSA
- Remains unbroken cryptographically
- Weaknesses known
- SHA-3 (replacement) under standardization

### GPU Mining
- GPUs designed for high-performance graphics
- high parallelism
- high throughput
- First used in Bitcoin ca. Oct 2010
- Implemented on OpenCl
- Later: hacks for specific cards
### GPU Mining Advantages
- Easily available, easy to set up
- Parallel ALUs
- Bit-specific instructions
- Can dirve many from 1 CPU
- Can overclock
### "Goodput"
Observation: *some* errors are okay (may miss a valid block)
Goodput: throughput x success rate
Worth over-clocking by 50% with 30% errors
### GPU Mining Disadvantages
- Poor utilization of hardware
- Poor cooling
- Large power draw
- Few boards to hold multiple GPUs
### FPGA Mining
- Field Programmable Gate Area
- First used for Bitcoin ca June 2011
- Implemented in Verilog
### FPGA Mining Advantages
- Higher performance than GPUs
- excellent performance on bitwise operations
- Better coding
- Extensive customization, optimization
### FPGA Mining Disadvantages
- High power draw than GPUs designed for
- frequent malfunctions, errors
- Poor optimization of 32-bit adds
- Fewer hobbyists with sufficient expertise
- More expensive than GPUs
- Marginal performance/cost advantage over GPUs
::: success
Bitcoin Mining ASICs dominate the industry right now

:::
### Bitcoin ASICs
- Special purpose
- approaching known limits on feature sizes
- Less than 10x performance improvement expected
- Designed to be run constantly for life
- Require signigicant expertise, long lead-times
- Perhpas the fastest chip dev ever

### Market Dynamics (2013/2014)
- Most boards obsolete within 3-6 months
- half of profits made in first 6 weeks
- Shipping delays are devastating to customers
- Most companies require pre-orders
- Most individual customers should have lost
- But the rising prices have saved them
### Professional Mining Centers
Needs:
- Cheap power
- Good network
- Cool climate
### The Future
- Can small miners stay in the game?
- Do ASICs violate the original Bitcoin vision?
- Would we be better off without ASICs?