The PC Part Numbers
Part-picker marketing rounds numbers up and rarely explains what they mean in practice. This page is the normalized decoder table: what a PSU's wattage rating really covers, what 80 Plus tiers actually certify, the honest RAM-speed and NVMe-generation gaming impact bands (not one exaggerated percentage), CPU cooler TDP matching, case airflow classes, GPU power connector ratings, and how to read a bottleneck calculator honestly. It is a reference dataset, not a buying guide — pair it with your exact component's spec sheet before you buy.
The one thing to know: PSU wattage marketing rounds up. A modern mid-range gaming PC (6-8 core CPU + one mid-range GPU) typically draws 250-450W at the wall under full load, well under what a 650-750W unit provides — the extra headroom exists for transient power spikes (GPUs briefly spike 1.5-2x their rated draw for milliseconds) and multi-GPU or heavy-overclock scenarios most builders will never hit. Buy for your actual GPU's official minimum-PSU recommendation plus modest headroom, not a round number that sounds safe.
The decoder table
| Metric | Category | Value / Range | What it means | Source type |
|---|---|---|---|---|
| Typical system draw (6-8 core CPU + one mid-range GPU) | PSU Wattage | ~250-450W at the wall under full load | The real power a common gaming PC pulls under full load — well under what a 650-750W PSU is rated for. | Manufacturer TDP specs + wall-meter measurement methodology |
| GPU transient power spike | PSU Wattage | ~1.5-2x rated board power, milliseconds | Why PSU headroom above average draw matters — spikes can trip an underrated PSU's protections even if average draw looks safe. | GPU manufacturer transient guidance + ATX spec tolerance |
| 80 Plus Bronze efficiency (50% load) | 80 Plus Tiers | ~85% AC-to-DC | Certifies efficiency ONLY — not build quality, protection circuitry, or reliability. | 80 Plus / Cybenetics certification standard |
| 80 Plus Gold efficiency (50% load) | 80 Plus Tiers | ~90% AC-to-DC | The common recommended tier for mid-to-high builds — meaningfully less wasted heat than Bronze. | 80 Plus / Cybenetics certification standard |
| 80 Plus Platinum efficiency (50% load) | 80 Plus Tiers | ~92% AC-to-DC | Matters more for 24/7 workstation or high-wattage builds than typical part-time gaming. | 80 Plus / Cybenetics certification standard |
| DDR5 4800→6000 MT/s gaming uplift | RAM Speed Reality | ~5-15% avg FPS (title-dependent) | The most impactful RAM-speed jump available at consumer prices, especially CPU-bound/1% lows. | Multi-title FPS benchmark methodology |
| DDR5 6000→8000+ MT/s gaming uplift | RAM Speed Reality | ~1-5% avg FPS, often within variance | Diminishing returns above ~6000 MT/s — costs proportionally more than the FPS gained. | Multi-title FPS benchmark methodology |
| NVMe Gen3 vs Gen4 load-time difference | NVMe Generation Feel | Typically under ~5% | Sequential-throughput spec gaps don't translate proportionally — loads are dominated by random 4K reads, not sequential speed. | Stopwatch/frame-time load benchmark methodology |
| NVMe Gen4 vs Gen5 load-time difference | NVMe Generation Feel | Typically under ~3%, often unmeasurable | Gen5 is even further from being the gaming bottleneck; drives often run hotter and need a heatsink to sustain rated speed. | Stopwatch/frame-time load benchmark methodology |
| Air cooler practical TDP ceiling | CPU Cooler TDP Matching | ~200-250W class (large dual-tower) | Match to the CPU's actual configured TDP/PPT rating, not just its model name. | Cooler manufacturer ratings + thermal benchmark methodology |
| 240/280mm AIO practical TDP ceiling | CPU Cooler TDP Matching | ~250-300W class, higher for 360mm | AIOs mainly earn their keep at the highest-TDP unlocked CPUs or where case clearance rules out a tall air tower. | Cooler manufacturer ratings + thermal benchmark methodology |
| Mesh-front vs glass-front temperature delta | Case Airflow Classes | ~3-8°C cooler, equal fan speed/noise | A real, measurable engineering tradeoff — the glass-front cost is aesthetics/dust filtering at a real thermal price. | Fixed-fan-speed comparative thermal/acoustic benchmark methodology |
| 8-pin PCIe connector rated capacity | GPU Power Connector Decoder | 150W per connector | Legacy connector, long safety track record; higher-power GPUs simply use multiple 8-pin connectors. | PCI-SIG ATX/PCIe power connector spec |
| 12VHPWR / 12V-2x6 rated capacity | GPU Power Connector Decoder | Up to 600W, single connector | Newer high-density connector with documented melting incidents tied to partial seating and tight cable bends. | PCI-SIG ATX 3.0/3.1 spec + published incident/mitigation reports |
| Bottleneck calculator resolution sensitivity | Bottleneck Myth Calibration | Same pair can be GPU-bound at 4K, CPU-bound at 1080p | A single percentage output can't know your resolution/settings — match GPU tier to target resolution instead. | Multi-resolution benchmark methodology (1080p/1440p/4K, same pair) |
RAM speed: the honest diminishing-returns curve
RAM speed has real but shrinking returns. Going from slow to mid-speed RAM (e.g. DDR5 4800 to 6000) can meaningfully help CPU-bound and integrated-graphics gaming scenarios; going from mid to top-tier speed (6000 to 8000+) delivers single-digit percentage gains in most games — often within margin of error. Capacity and dual-channel configuration (two sticks, not one) matter more for most builders than chasing the highest MT/s number on the box.
NVMe Gen3 vs Gen4 vs Gen5: can you feel it?
Gen4 vs Gen5 NVMe is not a felt difference in games or everyday use. Sequential read/write benchmarks look dramatically different on a spec sheet, but game load times and app launches are dominated by random 4K reads and the OS/game engine, not sequential throughput — most reviewers measure load-time differences in the low single-digit percent range, often unnoticeable without a stopwatch. Gen5 drives also run hotter and often need a heatsink just to sustain their rated speed. Buy Gen4 unless you have a specific large-sequential-transfer workload (video editing scratch disks, big asset pipelines).
CPU cooler TDP matching
A CPU cooler is matched to a TDP number, not a CPU model name alone — the same CPU model can ship in multiple power configurations (e.g. a 65W 'eco' mode vs a 105W unlocked mode), so check the specific SKU's TDP/PPT rating, not just the model family, before sizing a cooler. Air coolers rated for 150W+ TDP handle the vast majority of desktop CPUs without needing liquid cooling at all; AIOs earn their keep mainly on the highest-TDP unlocked CPUs or when case clearance rules out a tall air tower.
Case airflow classes: mesh vs glass front
Case airflow is a genuine engineering tradeoff, not just looks. A mesh front panel measurably improves intake airflow and lowers component temperatures versus a solid glass or plastic front — independent case reviews (GamersNexus-style thermal/acoustic benchmarking) consistently show mesh-front cases running several degrees cooler at the same fan speed and noise level as glass-front variants of the same case. The glass-front tradeoff is aesthetics and dust filtering, not a myth, but it is a real thermal cost.
GPU power connector decoder
GPU power connectors are not interchangeable by appearance alone. Legacy 8-pin PCIe connectors (used alone or in pairs) have a proven safety record; the newer 12VHPWR / 12V-2x6 connector (used on many current high-end GPUs) has had documented connector-melting incidents tied to partially-seated connectors and tight bend-radius cabling — full seating and avoiding sharp cable bends near the connector are the documented mitigations. Always use the adapter or native cable the GPU manufacturer specifies, not a generic third-party cable.
Bottleneck myth calibration
A 'bottleneck percentage' calculator that spits out one number from just a CPU and GPU model name cannot know your resolution, settings, or the specific game engine — the same CPU/GPU pair can be GPU-bound at 4K and CPU-bound at 1080p in the very same title. The honest framing: at higher resolutions the GPU matters more; at lower resolutions and higher frame-rate targets (esports titles, high-refresh monitors) the CPU matters more. Match your GPU tier to your target resolution class (see our build guides) rather than trusting a single bottleneck-percentage output.
Caveats — read before citing a number
- Bands, not guarantees. Every percentage range above is a typical band from independent benchmark methodology, not a promise for your exact hardware combination and settings.
- Check your exact SKU. The same CPU or GPU model name can ship in different power configurations across regions and revisions — verify the specific SKU's TDP/PPT and connector requirement.
- This table is engineering reference, not a build recommendation for any specific case/PSU/GPU combination — see our build guides for component-class shopping lists built on these facts.
- Standards and typical ranges shift. GPU power draw, connector standards, and NVMe generations are actively evolving; this decoder reflects the market as understood as of the version date below.
Methodology & versioning
Version 1.0 — published July 30, 2026. Facts are drawn from manufacturer specification sheets (PSU 80 Plus/Cybenetics certification listings, GPU/CPU official TDP and connector specs, PCI-SIG ATX power specifications) and independent benchmark methodology in the style of outlets like GamersNexus — fixed-fan-speed comparative thermal/acoustic testing, multi-title FPS averaging across resolutions, and stopwatch/frame-time load testing. We do not run our own lab benchmarks; this is a normalized facts reference built from published manufacturer specs and established independent-review testing conventions, not a lab result of our own. Corrections: if a spec changes or we find an error, this page and the CSV below are updated in place and the version/date bumped — see How We Evaluate for our full editorial policy.
License: This dataset is released under CC BY 4.0 — reuse it with attribution.
Cite this dataset: Rig Builder Lab, "The PC Part Numbers," version 1.0, July 30, 2026.
https://rig-builder-lab.pages.dev/pc-part-numbers/
Machine-readable download: the full table is available as CSV at /pc-part-numbers.csv, and a condensed digest is maintained in /llms-full.txt.
This page is general engineering reference information, not a compatibility guarantee for any specific component combination.
Frequently Asked Questions
A normalized reference table of the engineering facts behind PC build decisions — real PSU draw vs marketed wattage, what 80 Plus tiers actually certify, RAM speed's real-world gaming impact in bands (not one exaggerated number), the honest Gen3/4/5 NVMe feel difference, CPU cooler TDP matching, case airflow classes, GPU power connector ratings, and how to read (or ignore) a bottleneck calculator.
No. Wattage is a capacity ceiling, not a performance spec — a properly-sized 650W unit performs identically to an oversized 1000W unit for the same build. Buy to your GPU's official minimum-plus-headroom recommendation, not the biggest number on the shelf.
For most gaming and everyday use, no — the measured load-time difference versus Gen4 is typically under 3%, often unmeasurable without instrumentation. Gen5's real advantage is large-sequential-transfer professional workloads, and drives often run hotter and need a heatsink to sustain their rated speed.
Because it's a measurable thermal difference, not aesthetics-only: independent fixed-fan-speed testing consistently shows mesh-front cases running roughly 3-8°C cooler than glass-front variants of the same case at equal noise level.
No. This table normalizes general engineering facts and typical ranges. Always check your specific CPU's configured TDP/PPT, your specific GPU's minimum PSU and connector requirement, and your specific case's fan-mount count before buying.