Hard Drive

Hard Drives are special parts obtained from Crash Sites used to unlock Alternate Recipes (see below). Crash Sites can be located using Object Scanner after Radio Signal Scanning has been researched in the M.A.M..

Each Hard Drive can be researched in the M.A.M. and results in a choice of one of 3 alternate blueprints, chosen from the pool below.

There are 89 Crash Sites, which means a total of 89 Hard Drives can be obtained. Two Hard Drives can be used for engineer inventory expansions, leaving 87 for alternate recipes. Currently, there are 72 Alternate Recipes, leaving 15 unused.

Alternate Recipes
Alternate recipes generally require different input materials than the original, trading between raw material consumption, space, power, simplicity and availability of material.

The set of blueprints to choose from is determined randomly at the beginning of the scan. Because of this, the player can keep re-rolling to get the desired blueprint by saving the game before researching a hard drive, then loading the save and waiting for another 10 minutes if the choices are undesirable. The recipes are determined on the beginning of the scan and are only shown to the player after the research concludes.

The selected alternate recipes is unlocked immediately after it is chosen. All alternate recipes can be only used in factory buildings, none in the Craft Bench; therefore, parts like Compacted Coal cannot be hand-crafted.

To allow an Alternate Recipe to be shown up after a Hard Drive research, the prerequisites as shown below must be fulfilled, whether it is Milestone, Research or other Alternate Recipe. This means if a player builds a factory that requires certain alternate recipes that they have not yet unlocked, they may need to find more Hard Drives than they anticipated in order to unlock the prerequisites blocking their intended alternate recipes.

Note: It appears that there are several alternate recipes that can be unlocked at Tier 3, despite involving a fluid (Water) making them Refinery recipes, which is not unlocked before Tier 5.

In the table below, the Prerequisites are the conditions that are required for a recipe to be able to appear in the research result choices, while the Milestone in italic is the additional requirement that the recipe can actually be automated in a machine.

Important notes

 * The Hard Drive research is repeatable, as long as there are remaining alternate recipes to unlock.
 * Each alternate recipe can only be unlocked once, it will never appear in the selection screen again once it has been selected.
 * If you research a Hard Drive, and there is nothing more available to unlock, the Hard Drive will be returned to your inventory with the following message: "The analysis of Hard Drive is completed! No new research is available. Try again later after further progress. Your Hard Drive has been returned to you.".

Resource-efficient recipes
You should use these recipes when progressing towards the end game. These recipes are highly resource efficient, they get the most product out of every single raw resource input. Or if not, they usually are to be used in conjunction with other alternative recipes to be useful as a 'group'. Sometimes, these recipes can be very difficult to be set up due to their complexity, and usually that also means you need to provide a strong power grid before using them. Besides that, you probably need a lot of building space.
 * Bolted Frame: Significantly improved production speed with negligible amount of Iron Ore loss.
 * Casted Screw, Steel Screw: "Casted Screw" has the same ratio of Iron Ingots to Screws, but removes the need to make Iron Rods first, and produces 25% faster as well. Prioritize "Casted Screw" first for increased production speed. "Steel Screw" is ultimately more resource-efficient, producing nearly 5 times as many Screws per Iron Ingot when combined with "Solid Steel Ingot", at the cost of more steps in the production chain and requiring coal.
 * Caterium Computer mixed with original recipe: The alternate recipe is preferred, however Caterium can get used up quickly and this is where the original recipe comes in handy to make up for it.
 * Cheap Silica: Limestone is abundant, using it to reduce the load in Raw Quartz is almost a necessity.
 * Compacted Coal: Not an alternative really. Used for Compacted Steel Ingot and Gun Powder to improve resource usage and production speed, and mandatory for the production of Turbofuel using either recipe.
 * Copper Rotor: Increased production speed by mixing Copper into it.
 * Diluted Packaged Fuel: Adds Water to *triple* the Heavy Oil Residue -> Fuel conversion ratio. Combine with "Heavy Oil Residue" for extremely efficient Crude Oil -> Fuel conversion ratios. This recipe is part of a loop that maximizes the utilization of Crude Oil for power using "Turbofuel", and "Compacted Coal", or for Rubber and Plastic using "Recycled Rubber" and "Recycled Plastic".
 * Electrode Aluminum Scrap: Relieves the Crude Oil consumption. It also has a better conversion rate.
 * Encased Industrial Pipe: Uses ~33% fewer Steel Ingots per unit, but produces 33% fewer beams per minute as well. Saving on steel is worth the additional Assemblers. Stators, Steel Rotors and many other recipes also use Pipes rather than Beams, which can simplify production.
 * Gun Powder: All-round winner.
 * Fused Quickwire: Caterium is much more precious than Copper, so yes.
 * Heat Exchanger: Saves Crude Oil and Bauxite.
 * Heavy Encased Frame: All-round winner; only requires a little more Limestone.
 * Heavy Oil Residue: *Substantially* improves the Crude Oil -> Heavy Oil Residue conversion ratio. Combine with "Diluted Packaged Fuel" for extremely high Crude Oil -> Fuel ratios, which can be used for very efficient Turbofuel or Plastic/Rubber (via "Recycled Plastic"/"Recycled Rubber") production.
 * Infused Uranium Cell mixed with original recipe: The alternate recipe is preferred, use the original recipe to boost the production if Quartz and Caterium are insufficient.
 * Insulated Crystal Oscillator: A little bit of Crude Oil is worth it to save on Quartz.
 * Iron Wire mixed with original recipe. The original recipe is slightly more resource-efficient and is preferred, unless Copper is fully utilized. Can be used with Stitched Iron Plate for the most efficient Iron-only Reinforced Iron Plate production.
 * Nuclear Fuel Unit mixed with original recipe: The alternate recipe is preferred, unless Crystal Oscillators are insufficient.
 * Polyester Fabric: Necessary to automate the production of Filters.
 * Pure Caterium Ingot, Pure Copper Ingot, Pure Iron Ingot, Pure Quartz Crystal: Substantial increase in conversion ratio by just adding Water. Requires using Refineries for ore processing, though.  Recommend using "Copper Alloy Ingot" over "Pure Copper Ingot" until Copper Ore is fully utilized, due to production footprint and _substantially_ reduced production speed per building.
 * Radio Control System: Although Supercomputers seem to be difficult to produce, this recipe is actually an all-round winner.
 * Recycled Plastic, Recycled Rubber: More complex, but way better than original recipe. Use both along with Heavy Oil Residue and Diluted Packaged Fuel for extremely efficient Crude Oil to Plastic/Rubber production (~3 Rubber/Plastic per Crude Oil, compared to original 0.67 Rubber/Plastic per Crude Oil)
 * Silicon Circuit Board: Actually better than "Caterium Circuit Board" since no Oil is involved.
 * Solid Steel Ingot: Produces approximately 67% more Steel per Iron Ore (if also using Pure Iron Ingot).
 * Steamed Copper Sheet: Half the Copper Ingots per Sheet just by adding Water. Requires processing in a Refinery rather than a Constructor, however.
 * Stitched Iron Plate: The most resource-efficient recipe. Combining with "Iron Wire" removes the need for Copper Ingots, at the cost of a very small reduction in raw resource efficiency.
 * Turbofuel: Useful for pre-nuclear setup. "Turbofuel" is preferred over "Turbo Heavy Fuel", as it has a better conversion rate from Heavy Oil Residue. Combine with "Heavy Oil Residue" and "Diluted Packaged Fuel" for extremely efficient Fuel Generator supply, with the ability to run ~148 Fuel Generators (22,222 MW) from just 300 Crude Oil per minute.
 * Turbo Rigour Motor: Necessary for large scale Turbo Motor Production. The key point is to reduce the need for Radio Control Units which are also not easy to be mass-produced.
 * Wet Concrete: Double the conversion ratio just by adding water. Requires using Refineries for processing, though.

Situationally useful, but not resource efficient recipes
You're probably going to use a few of these recipes during the mid-game. They may provide small boost or even slightly worse resource conversion ratio compared to the base recipe, but their recipe simplicity, space compactness, or power reduction can prove them to be useful to save you in certain situations.
 * Biocoal, Charcoal: Useful if Coal is in shortage and Biomass and Wood are in excess. However, it is recommended to craft Wood into Biomass for other uses instead.
 * Bolted Iron Plate: A substantial boost in speed compared to original recipe, at the cost of ~10% more Iron Ingots per Plate. "Stitched Iron Plate" is a more resource efficient alternative.
 * Caterium Circuit Board: Can be useful in mid game, however Silicone Circuit Board is more efficient in the late game.
 * Quickwire Stator, Fused Wire: Useful in mid-game where Caterium is plenty. Take note that Caterium is a bit more rare than Copper, so in the long run these recipes will hurt your efficiency.
 * Coke Steel Ingot: A method to get rid of excess Heavy Oil Residue. Safety precaution such as an overflow system is recommended to prevent jamming the Oil production upstream.
 * Crystal Computer: Useful in mid-game where Quartz is still in excess. Caterium Computer is a more resource efficient alternative.
 * Iron Alloy Ingot, Copper Alloy Ingot: When paired together, they produce more ingots compared to separated production chains. In late-game, pure ingot recipes are more efficient. On their own, "Copper Alloy" is much more useful than "Iron Alloy", as Iron is more than twice as common as Copper, so effectively turning Iron into Copper is extremely useful mid-game.
 * Plastic Smart Plating: Involves Oil which is a limited resource, hurting its utility in late-game, but can be useful in mid-game as it is 5x faster and twice as efficient per Reinforced Iron Plate and Rotor used.
 * Polymer Resin: Greatly increases Crude to Polymer ratio and Polymer production speed, at the cost of Heavy Oil Residue or Fuel output. Can be useful for supplying a Polyester Fabric factory, but is substantially less efficient compared to the a Recycled Plastic/Recycled Rubber combo for producing Plastic and Rubber (see above).
 * Pure Aluminum Ingot: Removes the need for Silica (Raw Quartz) and decreased power consumption at the cost of 25% less ingots from the same amount of Scrap.
 * Rigour Motor: Useful in mid-game. In late-game, Crystal Oscillators are to be spent in more important recipes.
 * Silicon High-Speed Connector: Uses Raw Quartz instead Caterium Ore. Useful for mid-game where Quartz is still in excess.
 * Compacted Steel Ingot: Can be used to reduce Coal demand, as it requires only 45% as much Coal per Steel Ingot, at the cost of requiring an equal amount of Sulfur, and an Assembler making Compacted Coal for every 2.22 Foundries.
 * Steel Rod, Steeled Frame: Useful if Coal is plenty. Steel Rod in particular produces 3.2x as many Iron Rods per minute for the same number of Constructors, and produces 6 times as many Rods per Iron Ingot if using the "Solid Steel" alternative recipe, at the cost of requiring 1 Coal per 6 Iron Rods produced.
 * Steel Rotor: Shares the same types of ingredients as the default Stator recipe, which can significantly simplify the production setup. Utilizes less than half of the overall Iron at the cost of a little bit of extra Coal if combined with "Iron Wire". Faster production speed than the base recipe.
 * Turbo Heavy Fuel: Useful for pre-nuclear setup. Much simpler to set up than the normal Turbofuel recipe, however, it is far less resource efficient. Additionally, the default recipe can be greatly combined with more alternate recipes which aren't compatible with this one.

Inefficient recipes
You should avoid using these as their disadvantages are far greater than the advantages they provide. None of these recipes are resource effective.
 * High Speed Wiring: The complexity involved does not justify the speed boost.
 * Caterium Wire: Any Wire recipe that involves Caterium Ore as input are not resource effective. If you are going into these, use Fused Wire (see above) instead.
 * Coated Cable, Insulated Cable, Quickwire Cable: All involve Oil which is a limited resource. The usage of Refineries also means they will eat away a good chunk of your power capacity.
 * Coated Iron Plate, Steel Coated Plate, Adhered Iron Plate: All involve Oil which is a relatively rarer resource.
 * Electrode Circuit Board: This recipe will use up your Crude Oil quickly.
 * Electromagnetic Connection Rod: Increased production speed comes at the cost of adding Crude Oil and increasing usage of Caterium (or adding Quartz, if using alternate Silicon High-Speed Connector recipe).
 * Fine Concrete, Rubber Concrete: Limestone is abundant and there is no reason to use alternate recipes involving rarer resources.
 * Heavy Flexible Frame: Oil is more precious than Coal so there is no reason to use this.
 * Flexible Framework: Involves Oil which is a limited resource.
 * Seismic Nobelisk: Crystal Oscillators are used in more important recipes.
 * Signal Beacon: The requirement for Quartz and Coal does not justify its speed boost. Also, the original Beacon recipe can be purely Iron-based if Iron Wire is used.

Diluted Packaged Fuel cycle
This combination uses Heavy Oil Residue -> Diluted Packaged Fuel to increase the Crude Oil -> Fuel conversion ratio by 4.5x. This improved fuel ratio is then combined with Recycled Plastic and Recycled Rubber to produce 3 Plastic or Rubber per 1 Crude Oil input.

The fuel conversion can alternatively be used with Turbofuel and Compacted Coal to greatly improve energy generation, allowing a single oil node to supply over 11x as many Fuel Generators at maximum usage, compared to the normal Crude Oil to Fuel recipe. Even relative to directly using the Fuel produced by the Diluted Fuel combination, Turbofuel increases the number of generators that can be supplied by 2.78x, at the cost of requiring Coal and Sulfur input for the Compacted Coal. Final ratio is 148.15 Fuel Generators (22,222 MW) for 300 Crude Oil and 480 Sulfur and Coal per minute, which can be accomplished, via overclocking, off of a single Oil node of normal or pure quality, and a single node each of Sulfur and Coal at pure quality, or two each at normal quality, using Miner Mk.2's.

Nuclear Fuel
The base conversion rate of Uranium to Nuclear Fuel Rods is 100:1. Uranium Ore converts to Uranium Pellets at 1:1, Uranium Pellets convert to Encased Uranium Cells at 4:1, and Encased Uranium Cells convert to Nuclear Fuel Rods at 25:1. In total, this allows a single normal Uranium node (600/m using a Mk.3 Miner at 250%) to supply 30 Nuclear Power Plants, for a total of 75,000 MW of power. The alternate recipes Infused Uranium Cell and Nuclear Fuel Unit drastically improve this ratio. Infused Uranium Cells convert Uranium Pellets to Encased Uranium Cells at an 8:7 ratio (compared to 4:1, a 250% improvement), and Nuclear Fuel Unit converts Encased Uranium Cells to Nuclear Fuel Rods at a 50:3 ratio (compared to 25:1, a 50% improvement). This increases the number of fuel rods generated by 5.25x, allowing a single normal Uranium node to supply 157.5 Nuclear Power Plants, for a total of 393,750 MW of power. This increases the maximum sustainable nuclear power output from 225 GW to 1181 GW.

Alloyed Ingots
Using Iron Alloy Ingot and Copper Alloy Ingot together can yield significant increases in both for the same input. Normal smelting yields 1 Ingot per Ore input. Iron Alloy Ingot increases yield to 2.5 Ingots per 1 Iron Ore, at the cost of requiring an equal amount of Copper Ore. Copper Alloy Ingot increases yield to 2 Ingots per 1 Copper Ore, at the cost of requiring half as much Iron Ore. If used together, the net number of Ingots is increased by 2-2.5x, depending on ratios of usage between the two recipes.

Solid Steel Ingots
Using the normal recipe, 1 Steel Ingot is produced per Iron Ore and Coal input. Using Solid Steel Ingot combined with Pure Iron Ingot can increase this yield to 39 Steel Ingots for 14 Iron Ore and 26 Coal input. This is 2.79x as efficient with regards to Iron Ore, and 1.5x as efficient with regards to Coal.

Compacted Steel Ingot combined with Compacted Coal can be used instead to ease the demand on Coal at the cost of overall yield (relative to the Solid Steel Ingot recipe) and Sulfur. It provides 10 Steel Ingots for 6 Iron Ore, 3 Coal, and 3 Sulfur. Relative to the normal Steel Ingot recipe, this is 1.67x as efficient on Iron Ore, and 3.33x as efficient on Coal. Relative to the Solid Steel Ingot recipe, this produces only ~60% as many Steel Ingots per Iron Ore input, but requires only 45% as much Coal *per Ingot* (at the cost of requiring an equal amount of Sulfur).

As part of the Heavy Encased Frame chain, use Pure Iron Ingot -> Solid Steel Ingot -> Encase Industrial Pipes -> Heavy Encased Frame to see the cascading effect of resource saving. See Heavy Modular Frame for more info.

Iron Wire
Best paired with Stitched Iron Plate and default Beacon recipes to see its usefulness.

History

 * Patch 0.3.6: Introduced two alternate recipes for the Empty Canister
 * Patch 0.3.1.0: The 30 new alternate recipes added in 0.3 can now actually be unlocked
 * Patch 0.3:
 * Almost all recipes (including alternate recipes) have been adjusted
 * 30 new alternate recipes have been introduced (but aren't properly implemented and cannot be actually unlocked)
 * Patch 0.2.1.1: Clients should be able to see Hard Drives in Drop Pods again
 * Patch 0.1.14: Introduced a few alternate recipes
 * Patch 0.1.7:
 * Adjusted the Alternate Recipe for Compacted Coal
 * Old: 2 Coal + 2 Sulphur
 * New: 3 Coal + 3 Sulphur
 * Adjusted the Alternate Recipe for Turbo Fuel
 * Old: 5 Fuel + 2 Compacted Coal
 * New: 5 Fuel + 4 Compacted Coal
 * Patch 0.1.5:
 * Introduced several new alternate recipes
 * Alternate recipes can no longer be hand-crafted
 * Fixed the milestone cost of the Alternate Heavy Modular Frame
 * Reduced the Quickwire cost of Quickwire alternate recipes
 * Patch 0.103: Fixed the Hard Drive research crash
 * Patch 0.1: Adjusted a few alternate recipes
 * Patch Closed Alpha 4: Now researchable and gives Alternate Recipes