Methodology
FitMyPC.net uses transparent dimensional checks rather than treating one published maximum GPU length as a complete compatibility guarantee.
Length check
For a front-mounted radiator, FitMyPC.net deducts the selected radiator-and-fan thickness from the case's available GPU length. The graphics-card length must then be less than or equal to the remaining usable length.
Height and power-cable check
The selected GPU height is combined with a cable-space allowance. The default allowance depends on the connector profile stored for the card and can be overridden by the user. This is compared with the case's effective side-panel envelope.
Thickness / installation-envelope check
FitMyPC.net normally compares GPU cooler thickness with the case's available GPU thickness or slot-depth envelope. Where a manufacturer publishes a more conservative case-preparation or installation envelope, FitMyPC may store that planning envelope instead of treating the card's physical slot count as the required clearance. For example, NVIDIA lists the RTX 5090 Founders Edition as a 2-slot card but asks builders to provide a 61mm / 3-slot case-clearance envelope.
How FitMyPC.net reports a failed fit
A graphics card can have plenty of length clearance and still fail because its height plus power-cable allowance exceeds the case side-panel envelope, or because the card is too thick for the stored slot-depth envelope. Summary cards therefore report the limiting failed dimension rather than displaying a positive length margin beside an overall fail result. Exact compatibility pages continue to show every individual check separately.
Radiator position
Front mounting can directly consume the same longitudinal space as a graphics card, so the generic engine deducts front-radiator thickness from GPU length. Top and side radiator interference depends much more heavily on an individual chassis layout and is not silently assumed.
Manufacturer verification
Where FitMyPC.net displays a manufacturer-verified badge, the listed fields have been checked against an official manufacturer product page, technical specification or manual. Verification is field-specific: for example, GPU length and radiator support can be manufacturer verified while a case's effective side-panel cable envelope remains estimated. The source is linked directly so users can inspect it themselves.
Hardware specifications and product revisions can change. The verification date is stored with each sourced record, and current manufacturer documentation should still be checked before a final purchase.
Data confidence
Manufacturers do not publish every useful internal case dimension in a consistent format. FitMyPC.net therefore distinguishes reference data, user-entered data and estimated values. An estimated field should be treated as a planning aid, not as a manufacturer-certified specification.