Mnemocrystals are exotic formations of conditionally conductive matter found on several planets under the Æthereal Sun. While the original mnemocrystals were all natural formations, a process for synthetic manufacture exists.

Mnemocrystals are sometimes half-jokingly called Black Boxes, because while it it possible to predict (or even modify!) the output signals of a mnemocrystal based on input signals, it is not possible to trace the paths within an intact crystal. In fact, it appears that the signal propagate within the crystals at a slightly superluminal speed, based on the minimum recorded delay between input and output.

These properties made it possible to use properly treated mnemocrystals as the primary device used in calculations. In fact, the world of Æthereal Sun doesn't have computers as we humans know them, and uses mnemocrystals instead.

One interesting peculiarity regarding mnemocrystals is that their processing power and data storage scale non-linearly with mass. A desk-sized (that is, table-sized, not desktop-tower-sized) mnemocrystal is about as good as a early-mid-TL8 desktop, but one ten times as big is about 100 times as good. In other words, Æthereal Sun's mnemocrystals become better than human microprocessors at Macroframe size and larger.

Mnemocrystal Size-Types

This is a list of typical mnemocrystal sizes. Complexity is as per GURPS Ultra-Tech rules. Weight is in pounds. Size is a comparison, and assume sufficient space for maintenance (so a hall actually includes some corridors; the crystal core is solid and lacks any entrences though). Storage is the innate storage capacity of the device (multiply by 10 for a storage-only device with no processing power). Terminals is the the typical number of terminals (with a reservation of C3-equivalent processing power and storage on the server itself) that a given mnemocrystal supports; number with an asterisk means an inferior terminal - smaller, and not associating with that much processing power.

Type          Complexity Weight  Size     Storage Terminals Cost
Minicalc/PDA  -1         ½       palm     10MB    1*        100
Macrocalc     0          1½      big palm 100MB   1*        350
Medium        1          4       notebook 1GB     1*        1k
Large         2          13      desktop  10GB    1*        3½k
Microframe    3          40      desk     100GB   1         10k
Custom Rack   4          130     wardrobe 1TB     10        35k
Mainframe     5          400     room     10TB    100       100k
Large mainfr. 6          1,333   hall     100TB   1k        350k
Macroframe    7          4,000   storey   1PB     10k       1M
Large macro   8          13,333  house    10PB    100k      3½M
Megaframe     9          40,000  building 100PB   1M        10M
Progenitor    11+        400,000 enormous 1EB?    50M+      unique

Rough guidelines on what Complexity is comparable to:

Complexity    CPU        RAM        HDD        Program Size
-1            64 KHz     32 KB      10 MB      100 kB
0             512 KHz    256 KB     100 MB     1 MB
1             3 MHz      2 MB       1 GB       10 MB
2             32 MHz     16 MB      10 GB      100 MB
3             333 MHz    128 MB     100 GB     1 GB
4             5 GHz      1-2 GB     1 TB       10 GB

Note: Program Size denotes the typical size of a program of a given Complexity on the HDD. It does not account for the space required by large databases that may or may not be needed to work with some of the programs.

Mnemocrystal Modifications

Mnemocrystals accept some modifications similar to those accepted by Ultra-Tech computers:

  • Efficient: an abnormally efficient mnemocrystal, usually a rare natural formation; +1 Complexity, ×20 cost.
  • Ultra-Efficient: even more so, and definitely not a synthetic one; Progenitor is suspected to be of this type; +2 Complexity, ×500 cost.
  • High-Capacity: can run 50% extra programs at a time, and has +50% storage. ×1½ cost.
  • Cryptophillic: between natural predisposition and special treatment, this mnemocrystal is much more suited to searching its databases and breaking encryption; double Complexity only for the purpose of breaking encryption and searching its internal databases; ×20 cost, weight unchanged.

There are also other modifications, unique to Æthereal Sun:

  • Memory Only: this mnemocrystal has 10× as much memory as its Complexity would indicate, but it can only store data (it cannot process it). Data can still be overwritten. This crystal has a port or socket for connecting to a processing mnemocrystal; but nothing else; halve its volume. Cost ×1/10.
  • ROM: this mnemocrystal can only store data. It can be written to exactly once, and cannot be erased (except by destroying it). It has 100× as much memory as its Complexity would indicate. This crystal has a port or socket for connecting to a processing mnemocrystal, but nothing else; halve its volume. Cost is ×1/20 for an empty one, but if you're buying something on it (e.g. music, software), the price will be higher.

Renting processing power

It is possible to use a terminal and rent the processing power from a university or other group or individual with a large mnemocrystal. Prices vary depending on the crystal's size - the bigger, the cheaper; sizes from Mainframes and Large mainframes are the most common; various large Universities might own Macroframes.

Rental is usually agreed to in advance, and for prolonged periods (less than a week commonly is considered silly; big frame owners prefer to have a predictable payoff).

Type          Complexity Investment All/mo   C1/mo  C4/mo C4/day

Microframe    3          10k        120      1.2    -
Custom Rack   4          35k        360      0.36   360   12
Mainframe     5          100k       1,200    0.12   120   4
Large mainfr. 6          350k       3,600    0.036  36    -
Macroframe    7          1M         12k      0.012  12    -
Large macro   8          3½M        36k             3.6   -
Megaframe     9          10M        120k     0.0012 1.2   -
Investment is the full price of a mnemocrystal;
All/mo is the rental cost per month of the whole mnemocrystal.
C1/mo is the cost of C1 worth of processing power per month.
C4/mo is the same for C4 (the most common amount processing power rented).

Spaceships and shipboard MCs

Due to the peculiar progression, Spaceships do not have the standard computer networks found in G:SS. Instead, a Control Room has a single mnemocrystal that takes up no more than half the actual cost and mass of the Control Room. Most functions on a ship rely only partially on the central mnemocrystal, thus other game effects are mostly the same as with standard Control Rooms.

Encryption / Cryptography

Effectively, encryption is TL9 with adjustments for nonlinear MC Complexity scaling.

When calculating decryption time, take the encrypting software's complexity (maximum 4), and subtract it from the decryption equipment's Complexity; the result is your Complexity Advantage. For a Complexity Advantage of +6, the time between rolls is one hour. For each additional level of Complexity Advantage, reduce the time taken tenfold. For each level less, increase it tenfold for normal MCs or threefold for Cryptophillic MCs.

Remember that many devices will only be able to spare a negative Complexity for their encryption; a typical phone will provide -2.

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