What is ECC memory?
Error-correcting code memory (ECC-RAM) is a memory that recognizes and can correct certain types of internal data corruption. ECC memory also checks data in the memory that could be corrupted and prevents 99.988 percent of the most common memory errors.
What types of memory errors exist?
» Hard errors, also known as single bit errors:
This type is relatively easy to determine and correct, as the error occurs repeatedly. This is referred to as a constant correlation function.
» Soft Errors:
This type occurs more frequently than assumed and is difficult to detect. Soft errors occur when a program bit reads out an incorrect return value but still functions correctly.
Where are ECC memories used?
ECC memory is mainly used for workstations and servers where data errors cannot be tolerated under any circumstances (e.g. construction, design, science, financial analysis). Compared to the alternatives, ECC memory is somewhat slower (2-3 percent) and also somewhat more expensive (around €22 more for a 2x 4GB memory configuration).
What effects can a memory error have?
The occurrence of a memory error can have four possible consequences. The problem with this is that the consequences do not all have to occur at once or are not noticed by the user.
- A memory error in a location used for pixel display can change a pixel color from red to blue. An error of this type may be invisible and have almost no consequences.
- A storage error in a location that is not used will not cause any complications or consequences.
- A memory error in the form of a bit flip that causes a 1 to become a 0 is significant. For example, a portfolio trading strategy could have a significant negative impact if the bit flip occurred unknowingly. The result would be trading to the wrong solution.
- Ein Speicherfehler, der in einem vom Betriebssystem benutztem Teil des Speichers auftritt, kann verheerend sein. Resultat kann ein Bluescreen des Betriebssystems sein, also ein kompletter Stillstand. Vorausgegangene Arbeiten, die kurz vorher nicht auf einem Nichtflüchtigen Datenträger gesichert worden sind, gehen dabei verloren. Monetär ausgedrückt bedeutet dies, dass die Summe aus Neuerstellung der Arbeit seit dem letzten Speicherpunkt, plus Zeit zur Reparatur des System, plus die Opportunitätskosten der verlorenen Arbeit in der Zeit der Reparatur schnell 500 € übersteigen können (1h + 2h + 2h = 5h à 100 € / h).
What is the chance of a memory error?
The chance of a memory error is higher than you might think, even if they are not noticeable. The following studies show the risk:
- According to Google, a memory error will occur on one in three computers.
- According to Google, one in three computers will experience a memory error, and according to AMD, a 4 GB system memory will have a memory error at least once a week. If more memory is available, the risk of an error also increases.
- According to LamdaDiode.com, a computer has a 96 percent chance of a memory error every three days.
Is the investment in ECC memory worth the money?
As a PC gamer you probably don't care about memory errors, but as a professional user who is involved in development, modeling, simulation, analysis, design or other activities and has to make important decisions based on their work, the answer should be “yes”.