BTO vs. Self-Built PCs: Compare Total Cost, Warranty and Your Work
Compare BTO and self-built PCs with matched parts, OS, shipping and warranty. Account for reused parts, setup effort and repair support before you buy.
Read guide →PC building, parts and value comparisons
Compare the whole platform cost, including motherboard, memory, power supply and case. Read the benchmark conditions and price-check date before applying a ranking to your games or applications.
Before choosing a task
- Choose the resolution, games or creative apps, required features and spending limit.
- Match exact models against CPU support, BIOS, memory type, case clearance and power connectors.
- Recheck prices and stock, then compare the complete build cost and warranty.
Compare the options
B650 vs. B850 vs. X870: Check USB4, M.2 Sharing and CPU Support
Compare B650, B850 and X870 using AMD and board specifications. Check USB4, GPU and M.2 lane sharing, SATA ports and CPU support before choosing a board.
Read guide →Air cooler or AIO? Choose by case clearance, noise and maintenance
Compare air coolers and AIOs by workload, noise, RAM clearance and radiator fit, with concrete sizing examples, total-cost checks and practical fault-diagnosis steps.
Read guide →PCIe 4.0 or 5.0 SSD for gaming? Check load times, capacity and slot sharing
Choose a PCIe 4.0 or 5.0 gaming SSD using measured load times, capacity, sustained writes and cooling needs, then check shared M.2 lanes and the full upgrade cost.
Read guide →DDR4 vs. DDR5: Choose for a New Build, Reused RAM and Upgrade Cost
Choose DDR4 or DDR5 around your platform and reused parts. Check board compatibility, memory kits and the full upgrade cost before replacing your RAM.
Read guide →DDR5 with Two or Four DIMMs: Compare Upgrade Speed Limits and Kits
Compare two- and four-DIMM DDR5 upgrades. Check CPU speed limits, tested kit populations, mixing restrictions and capacity verification before buying RAM.
Read guide →Integrated vs. Discrete Graphics: Check Workloads, CPU Models and Outputs
Choose integrated or discrete graphics by checking workloads, exact CPU graphics, shared memory, display ports and upgrade costs before buying a card.
Read guide →1080p, 1440p or 4K: Plan a Gaming Monitor and GPU Budget Together
Compare 1080p, 1440p and 4K using target FPS, refresh rate and GPU evidence. Check port limits and the total monitor, GPU and cable cost before buying.
Read guide →ATX vs microATX vs Mini-ITX: choose a PC case and motherboard
Compare ATX, microATX and Mini-ITX by board size, expansion and case clearance. Check GPU, cooler and PSU fit, then compare the complete build cost.
Read guide →Intel B860 vs. Z890 vs. H810: Choose an LGA1851 Motherboard by CPU Support, M.2, USB and Overclocking
Compare Intel H810, B860 and Z890 for Core Ultra 200S using Intel's own specification pages: CPU PCIe lanes, chipset USB and SATA limits, memory overclocking and Thunderbolt 4 implementation, plus when to keep an LGA1700 B760 or Z790 board.
Read guide →DisplayPort vs. HDMI for 144Hz, 4K and 240Hz Monitors: Check Ports, Cables and GPU Support
Decide whether to connect a 144Hz, 4K or 240Hz monitor over DisplayPort or HDMI using VESA and HDMI Forum bandwidth figures, GeForce RTX 50, Radeon RX 9070 and Arc B580 output specifications, LG and ASUS monitor input conditions and certified cable names.
Read guide →Choosing Case Fans: 120 mm vs. 140 mm and PWM (4-pin) vs. DC (3-pin) Compared from Official Specifications
Before adding case fans, check the case's mounting sizes (120 mm / 140 mm), how 4-pin PWM and 3-pin DC control differ, and how to read airflow against static pressure, with a same-series 120 mm and 140 mm comparison.
Read guide →Choosing a UPS for a Desktop or Custom-Built PC: Why Sine Wave Output Matters and How to Size VA and W
Sizing a UPS for a desktop PC: why PFC power supplies and square-wave output conflict, how to size by both VA and W with headroom, how much runtime to allow for a shutdown, and how the delivery methods differ.
Read guide →M.2 SSD heatsinks: clearance, warranty terms and the PS5 requirement decide bundled or bare
Whether to buy an SSD with a heatsink is usually settled by clearance and warranty wording rather than by comparing cooling. Check Samsung’s published heights and warranty note, the power figures, and the PS5 size limits.
Read guide →Onboard audio or a USB DAC/headphone amp: work out the voltage your headphones actually need
Headphones need voltage, not just "an amp". Put the two sensitivity conventions manufacturers publish onto one scale, compare the result with the output Creative and FiiO state, and see what a motherboard sheet omits.
Read guide →Check a laptop's upgradeability before you buy: soldered memory, M.2 slot count and battery capacity
Whether a laptop’s memory and storage can be expanded later is published before you buy. Learn which rows of Lenovo PSREF and Dell specification sheets state soldered memory, M.2 slot count and battery capacity.
Read guide →Buying a second-hand graphics card: the warranty, what to check, and what cannot be checked
A used GPU's warranty does not automatically come with the card. Check what NVIDIA and GIGABYTE publish about who covers it, why an auction receipt may not count as proof, and what to measure before you pay.
Read guide →Do you need a Copilot+ PC? The 40 TOPS / 16 GB / 256 GB requirement set, and whether your software runs on an Arm model
"AI PC" and "Copilot+ PC" are not the same claim. Here are the three hardware requirements Microsoft publishes, the conditions attached to each advertised feature, and where x86 emulation on Arm stops.
Read guide →How to read a CPU model name: Core Ultra and Core suffixes, and why the same model performs differently
How to split a spec-sheet name such as Core Ultra 7 165H or Ryzen AI 7 350 into tier, generation and suffix, and why two laptops with the same model number are not the same machine, using only what Intel and AMD publish themselves.
Read guide →How many external displays can you actually connect? GPU limits and the two kinds of dock
Buying a dock does not automatically add screens. The limit is set in three places: the GPU's maximum simultaneous displays, whether video is present on the port at all, and which kind of dock you bought. Includes how differently NVIDIA and AMD publish the figure.
Read guide →DDR5 CUDIMM explained: what the on-module clock driver changes, and how to check board support
Some DDR5 modules are labelled CUDIMM. The difference from an ordinary UDIMM is one part - a clock driver on the module - and whether you can use one is decided by the CPU and the board. This guide covers the JEDEC standard names and how to read a motherboard's memory row.
Read guide →CAMM2 and LPCAMM2: the third kind of laptop memory, and what it does and does not tell you about upgrades
Some laptop specification sheets now say LPCAMM2 or CAMM2. It is a third form, neither soldered nor SO-DIMM, and the DDR5 and LPDDR5 versions are not interchangeable. This guide reads JEDEC's standards for the distinction and for what upgradeability actually depends on.
Read guide →Before buying a used business PC: how to read Windows 11's supported-CPU lists, and what "activated" does not prove
There is only so much you can check on an ex-lease business PC before it arrives. This guide separates what Microsoft's supported-processor lists are actually for, what Windows activation does not guarantee, and whether TPM is absent or merely switched off.
Read guide →DDR5 on-die ECC is not ECC memory: how to check whether your CPU and motherboard actually accept ECC modules
"DDR5 has ECC built in, so you no longer need ECC memory" mixes one true fact with a substitution. This guide separates the two, names the exact spec-sheet fields that decide the question, and shows a case where two CPUs from the same generation answer differently.
Read guide →Can a Windows licence move to a new PC? The two acquisition routes section 4 of the licence terms separates
"OEM cannot be moved, retail can" — where in the text does that come from? This guide reads section 4 of the Windows 11 licence terms Microsoft publishes, in both the English and Japanese editions, and sets out what each route is permitted to do and what conditions are attached.
Read guide →Your DDR5-8000 kit boots at the default speed: XMP, EXPO, CPU rated memory speed and warranty wording
The DDR5-6000 or DDR5-8000 on the box is the speed a profile targets, not the speed the kit boots at. Read Intel's and AMD's published CPU memory speeds, the difference between XMP and EXPO, and the warranty wording each vendor actually prints, then check in that order before buying.
Read guide →There are two kinds of PSU "Gold": what 80 PLUS and Cybenetics measure, and what neither of them measures
Gold and Platinum on a PC power supply cover conversion efficiency and power factor at stated load points, and nothing else. Read the 80 PLUS tier tables, the Cybenetics ETA (efficiency) and LAMBDA (noise) criteria, and see why the same word means different things.
Read guide →Before buying a GPU for streaming or recording: read the NVENC generation, count, session limit and AV1 column
Streaming and video export use the GPU's video encoder, not its 3D cores. NVIDIA publishes a per-board support matrix where AV1 support and the concurrent-session limit are written down. This guide explains the columns and shows what the Intel side does and does not tell you.
Read guide →Before you buy a second SSD: the M.2 slots on your board are not interchangeable
On the same board, M.2 slots differ in PCIe generation and lane count, in the SSD lengths they accept, and in whether they work at all with the CPU you installed. Four official motherboard spec pages, read side by side, to show which four lines decide your second drive.
Read guide →Your case says 20Gbps on the front Type-C. Your motherboard may not agree
A case spec sheet that promises a 20Gbps front Type-C port describes the case. What the port actually runs at is set by the internal connector on the motherboard. One case and three boards, read from official pages, and the lines to compare before you buy either.
Read guide →Can you add Thunderbolt to a desktop? Onboard and add-in card need different things
Before buying a Thunderbolt dock or drive, check whether the desktop has a port for it. A board that has it built in and a board that needs an add-in card have different requirements — a dedicated header, a PCIe slot, video fed in, and auxiliary power. Taken from official specification pages.
Read guide →Before buying an expansion card: an x16-shaped slot can run at x1, and M.2 carrier cards need bifurcation
A PCIe slot's physical size is not its lane count. And a card that carries several M.2 SSDs only presents all of them if the board and CPU can split the slot. Three motherboard spec pages and a maker FAQ, turned into the lines to read before you buy.
Read guide →Do you need to buy a TPM module? Discrete, integrated and firmware TPM, and what actually requires one
A TPM header on the motherboard invites you to buy a module. Microsoft states that Windows uses any compatible TPM the same way and takes no position on how one should be implemented. The three implementations, the usual reason a TPM cannot be found, and which features really need one.
Read guide →Three ceilings to check before adding memory: your Windows edition, the board, and what is actually usable
More than one ceiling applies when you add RAM. Windows 11 Home stops at 128 GB, each motherboard publishes its own maximum, and installed capacity is never the same as usable capacity. The three, read from the official pages, in the order they bite.
Read guide →CPU value in Japan, September 2026: five gaming candidates ranked
Compare five CPUs using Japanese prices checked on September 19, 2026 and one gaming benchmark table, plus two alternatives and motherboard and RAM budget examples.
Read guide →GPU value ranking, September 2026: ten models at Japanese retail prices
Compare ten GPUs using Japanese prices checked on September 19, 2026 and a common benchmark suite. See 1080p and 1440p value, VRAM limits and buying checks.
Read guide →Follow the steps
Check PC-Part Compatibility Before Buying: CPU, BIOS, RAM, Case and Power
Check CPU and BIOS support, RAM type, GPU and cooler clearance, and PSU connections before buying PC parts. Verify exact models and configuration limits.
Read guide →How to Choose a PC Power Supply: Wattage, ATX 3.1 and GPU Cables
Choose a PC power supply using the exact GPU requirements. Check wattage, ATX revision, approved cables, case clearance and what efficiency ratings mean.
Read guide →Disposing of an old PC in Japan: the PC Recycle Mark, maker take-back, the small appliance route, and self-built machines
A PC often cannot go out with household waste in Japan. Here are the two collection routes - maker take-back, where the PC Recycle Mark decides whether a fee applies, and small home appliance recycling - plus self-built PCs and who erases the data.
Read guide →After assembly: diagnose startup and hardware problems
Choose the symptom you can observe: no power, a diagnostic LED, a missing device or a temperature warning. Each guide explains the checks and when to seek support.
- PC will not POST with a DRAM LED: check memory on an ASUS motherboard
- PC crashes after enabling XMP or EXPO: isolate the memory profile in ASUS BIOS
- M.2 SSD missing in BIOS: check SATA/NVMe support and the correct slot
- CPU FAN Error on an ASUS PC: check the CPU_FAN connection and RPM
- No display after a GPU upgrade: check connections and power when BIOS is also missing
- PC will not boot after a CPU swap: check ASUS CPU support and required BIOS
- PC power button does nothing: check the PSU switch and PWR_SW wiring
- CPU Over Temperature Error at startup: check cooling and cooler installation