Glossary

Dollars per gigabyte is the eligible street price divided by the product's advertised capacity in gigabytes.

For a 32 GB memory kit priced at $96, the calculation is:

$96 / 32 GB = $3.00/GB

For RAM, the capacity is the total kit capacity, so a 2 x 16 GB kit is 32 GB. For an SSD, we use the manufacturer's advertised capacity rather than converting it into the lower capacity an operating system may display after formatting. That keeps product labels comparable.

$/GB is a comparison aid, not a quality score. It does not account for RAM speed or timings, SSD controller and NAND, endurance, warranty, form factor, or whether a capacity is useful for your build.

Dollars per terabyte is the same calculation at a larger unit:

eligible street price / advertised capacity in TB

It is usually easier to read for SSDs and other storage products. A 2 TB SSD at $140 is $70/TB. We do not mix advertised decimal capacity with an operating system's binary-capacity display inside one comparison.

As with $/GB, a lower result means more advertised capacity per dollar. It does not mean the drive is faster, more durable, or better suited to a workload.

Dollars per core is a CPU's eligible street price divided by its number of physical processor cores. Threads are not counted as cores.

This ratio needs context on hybrid processors. A performance core and an efficiency core do not deliver identical performance, and two CPUs with the same core count can differ substantially in architecture, clock behavior, cache, power, and application results. We use $/core as a capacity ratio, not as a substitute for benchmarks.

The numerator matters too. $/core based on a live street price is not comparable with $/core based on an Intel RCP or a launch MSRP unless both are labelled.

80 PLUS is a power-supply efficiency certification program. Its levels, including Standard, Bronze, Silver, Gold, Platinum, Titanium, and the data-center-focused Ruby level, indicate that a tested unit met the program's efficiency requirements for its input-voltage and product class. The official program publishes its rating information and certified-product records.

An 80 PLUS badge is not a noise rating, teardown judgment, component-quality grade, warranty score, or guarantee that every retail revision shares the tested platform. It answers a narrower efficiency question.

Cybenetics ETA is also an efficiency certification, but its published method averages measurements across a much broader operating range and also considers factors such as power factor, standby-rail efficiency, and vampire power. The exact class thresholds depend on input voltage. See the official ETA method.

Cybenetics LAMBDA is a PSU noise certification. It is separate from ETA because efficiency and acoustic output are different properties. A PSU can score well on one and less well on the other. Cybenetics describes both programs in its certification FAQ.

We keep 80 PLUS, ETA, and LAMBDA as separate fields. None is rewritten into a PSU tier judgment. Reuse of Cybenetics data also remains subject to verified reuse terms; a public database and CSV export do not by themselves establish a commercial licence.

MSRP means manufacturer's suggested retail price. It is a manufacturer reference for a retail product, usually associated with launch or a direct-store listing. It is not proof that retailers sold the product at that price, and it may cover only products the manufacturer sells directly.

RCP means Recommended Customer Price, Intel's term. Intel states that RCP is pricing guidance rather than a formal offer and that its published prices typically represent 1,000-unit direct-customer quantities. It is therefore a distributor reference, not a consumer checkout price. See Intel's RCP explanation.

Street price is an eligible price actually offered by a named merchant at the displayed “as of” time, subject to the stated condition, seller, shipping, tax, and availability treatment. It can be above or below MSRP or RCP.

These labels are not interchangeable. A “20% below RCP” statement compares a retail offer with a reference, not with a former retail sale. A “20% below its own 90-day median” statement compares street observations with street observations.

Both are indexes published by the US Bureau of Labor Statistics, and neither is a per-SKU dollar price.

PPI, the Producer Price Index, measures average changes over time in selling prices received by domestic producers. Our semiconductor, storage-device, printed-circuit, computer-manufacturing, and weak PSU proxies are PPI series.

CPI, the Consumer Price Index, measures average changes over time in prices paid by consumers for a defined basket of goods and services. Our broad computers-and-peripherals backdrop is a CPI series.

PPI and CPI can move differently because their scope, transaction point, import treatment, and weighting differ. BLS explains those differences in its PPI and CPI comparison.

An index level is meaningful relative to the same series at another time. A PPI value of 180 does not mean a motherboard costs $180. A 10% change in a broad semiconductor PPI also does not mean every CPU, GPU, or RAM kit changed by 10%.

Percentile position tells you where the current eligible price falls among that same product's eligible observations inside the stated window.

A position at the 20th percentile means the current price is near the low end of that observed distribution. Roughly 20% of observations are at or below it and roughly 80% are at or above it. A position at the 80th percentile places it near the high end.

Percentile is a rank, not a percentage discount. The 20th percentile does not mean “20% cheaper.” It also does not predict the next price. A product can remain at a high percentile while prices keep rising, which is why percentile alone never creates a buy-or-wait recommendation.

The window and observation count are part of the figure. A percentile based on 20 observed days is not presented as a 90-day or 365-day position.

Boxed CPUs are retail-packaged products sold under a boxed product identity. Tray CPUs are typically supplied through OEM or bulk distribution channels. Packaging, included accessories, seller support, manufacturer warranty treatment, and part numbers can differ. Intel documents the distinction in its boxed and tray processor guide.

We therefore treat tray and boxed listings as different product identities. A lower tray price does not replace the boxed price in a boxed-product history, even when the silicon name is the same. The listing must say which form is being priced.

XMP, Intel Extreme Memory Profile, stores predefined memory speed, timing, and voltage settings that a compatible system can apply instead of requiring each value to be entered manually. Intel describes XMP as memory overclocking and notes that compatibility depends on the module, processor, motherboard, and firmware. See Intel's XMP guide.

EXPO, AMD Extended Profiles for Overclocking, is AMD's profile system for DDR5 memory used with supported Ryzen platforms. AMD also classifies enabling these profiles as overclocking. See AMD's EXPO documentation.

A kit may advertise XMP, EXPO, or both. The badge tells you which stored profile ecosystem the kit supports; it does not guarantee that every motherboard and processor combination will run the advertised setting. We keep the profile type in the product identity because two otherwise similar kits can target different platform behavior and should not be merged solely by capacity and headline data rate.