A professional desktop PC repair service handles problems that laptops and phones never face. Desktop computers use modular components — a separate power supply unit, a dedicated graphics card, a socketed processor, and multiple drive bays — each one individually replaceable. When a desktop fails, the repair is usually about identifying which specific component died and swapping it, rather than replacing an entire sealed assembly. This is what makes desktop repair both more affordable and more powerful than laptop repair in many situations.
At PC Mobile, our technicians diagnose and repair desktop towers, gaming PCs, HP and Dell all-in-one desktops, iMac systems, and custom-built computers. We also perform desktop upgrades that extend your system’s life by years — GPU, RAM, SSD, and power supply upgrades are our most popular desktop services. Every desktop repair comes with our 30-day warranty on parts and labor.
Desktop computers and laptops may both run Windows, but they are engineered very differently. These differences directly affect how repairs are performed, what they cost, and what upgrade options are available.
iPhone X and newer
The biggest advantage of a desktop PC is modularity. Unlike a laptop where the processor, RAM, and often the storage are soldered to one motherboard, desktop components are designed to be individually removed and replaced. Your power supply can be swapped without touching anything else. Your graphics card slides out of a slot. Your RAM clicks in and out. Your hard drive or SSD connects with a cable. This modularity means desktop repairs are often faster, simpler, and less expensive than the equivalent laptop repair — because we replace only the failed part, not the entire board.
Power Supply
Every desktop PC has a dedicated power supply unit (PSU) that converts wall electricity into the voltages your components need. Power supply failure is one of the most common reasons a desktop computer stops turning on entirely. A failing PSU can also cause random shutdowns, system instability, and even damage to other components like the motherboard or GPU if it delivers unstable voltage. Laptops do not have a separate internal PSU — they use an external adapter. Power supply diagnosis and replacement is a desktop-specific repair that we handle daily.
Desktop Computers
Desktop towers
If your desktop shows screen artifacts (colored lines, blocky patches, flickering), crashes during graphically demanding tasks, or outputs no display at all, the graphics card may have failed. We test your GPU in isolation, verify the issue is not the monitor or cable, and replace the card if needed. For gaming PCs, we also diagnose GPU thermal throttling caused by dried thermal paste or clogged heatsink fins on the card itself.
The motherboard connects every component in your desktop. When it fails, the symptoms can mimic other component failures — random shutdowns, failure to boot, USB ports not working, or no display output. We perform board-level diagnosis to determine whether the motherboard itself has failed or if the issue is actually the PSU, RAM, or GPU. Motherboard replacement in a desktop is more affordable than in a laptop because desktop motherboards are standardized sizes (ATX, Micro-ATX) and readily available.
Desktop computers can hold multiple drives simultaneously — a fast SSD for your operating system and a large hard drive for storage. We upgrade desktops from slow spinning hard drives to solid-state drives, clone your existing data so nothing is lost, and configure the system to boot from the new SSD. Desktops often have empty drive bays that allow adding storage without removing anything, which is not possible on most laptops.
Desktop RAM slots are easy to access and upgrade. Most desktops have two to four RAM slots, often with room to expand beyond what was installed at the factory. Adding RAM allows your desktop to handle more open programs, browser tabs, and multitasking without slowing down. We check your motherboard’s maximum supported RAM, match the correct type and speed, and install it — typically in under 15 minutes.
Desktop monitors are separate devices with their own power boards, backlights, and display panels. When a monitor goes dark, shows flickering, or displays no signal, the problem could be the monitor itself, the cable, the GPU, or the desktop’s video output port. We diagnose which link in the chain has failed. Monitor-specific repairs include backlight replacement, power board repair, and cracked panel replacement. We also help determine whether repairing your monitor or replacing it is the more cost-effective choice.
Desktop PCs are just as vulnerable to viruses, spyware, and ransomware as laptops. We perform full system scans using professional-grade tools, remove all malicious software, clean up registry modifications, and help you set up basic protection. Desktop-specific malware concerns include cryptomining trojans that hijack your GPU for cryptocurrency mining — a problem that primarily affects desktop systems with dedicated graphics cards.
Blue screen errors, boot loops, “Preparing Automatic Repair” loops, and failed Windows updates are common desktop issues. We repair Windows 10 and Windows 11 installations without unnecessary factory resets, preserving your data and settings. When a clean installation is truly needed, we perform a full backup first.
We also perform gaming PC upgrades — GPU upgrades to the latest generation, PSU upgrades to support more powerful components, additional case fans or liquid cooling installation, RAM expansion for streaming and content creation, and NVMe SSD upgrades for faster game loading. If you built your gaming PC a few years ago and want to bring it up to current standards without starting from scratch, we can help you plan and execute the right upgrades for your budget.
HP Pavilion (consumer), HP ENVY all-in-one (built-in display), HP Omen (gaming), HP EliteDesk and ProDesk (business). HP desktops are the most commonly repaired desktop brand we see. Power supply failures and hard drive failures on aging HP Pavilion systems are our most frequent HP desktop repairs.
HP Pavilion (consumer), HP ENVY all-in-one (built-in display), HP Omen (gaming), HP EliteDesk and ProDesk (business). HP desktops are the most commonly repaired desktop brand we see. Power supply failures and hard drive failures on aging HP Pavilion systems are our most frequent HP desktop repairs.
Lenovo ThinkCentre (business), Lenovo IdeaCentre (consumer), Lenovo Legion Tower (gaming). ThinkCentre desktops are popular with small businesses and are built for reliability, but PSU and storage failures still occur after three to five years of daily use.
Apple iMac (all generations including Intel and Apple Silicon M1/M2/M3/M4 models). The iMac is a desktop computer with the display, computer, and speakers built into a single unit. iMac screen replacements are complex because the Retina display is bonded to the aluminum chassis with strong adhesive. We repair iMac screens, replace internal storage, diagnose logic board issues, and recover macOS installations. iMac repair overlaps with our Apple expertise from MacBook repair, but the internal layout and screen construction are completely different from a MacBook.
We repair and upgrade custom-built desktop PCs with no brand restrictions. Whether your system was built by you, a friend, or a custom PC shop, we diagnose and fix it using the same component-level approach. Custom PCs sometimes use non-standard configurations that require extra diagnostic time — we handle that without issue.
The most common cause is a failed power supply unit (PSU). Unlike laptops that use external power adapters, desktops have internal power supplies that can fail after three to five years. Other possible causes include a faulty power button, a dead motherboard, or a short circuit. We perform a free diagnostic to identify the exact cause.
Yes. We diagnose and repair gaming PCs including GPU failures, PSU replacements, thermal paste reapplication, fan and cooling system service, and RAM or storage issues. We also perform gaming PC upgrades — GPU, PSU, cooling, RAM, and SSD upgrades to keep your system current without building from scratch.
Try connecting a different monitor or TV to your desktop using the same cable. If the second display works, your monitor is the issue. If neither display works, the problem is likely your desktop’s GPU, video port, or motherboard. We diagnose this during our free assessment and tell you exactly which component has failed.
Often, yes. Desktop components are modular and standardized, so they are easier to source and replace individually. A desktop power supply replacement, for example, is significantly less expensive than a laptop motherboard repair for a similar symptom (computer won’t turn on). Desktop RAM and storage upgrades are also cheaper and faster to install than the equivalent laptop upgrades.
In almost all cases, yes. Desktops are the most upgradable computers available. The most impactful upgrades are replacing a hard drive with an SSD, adding RAM, and upgrading the graphics card. We assess your current system, recommend the most cost-effective upgrades for your needs, and install everything. In many cases, the right upgrades make a five-year-old desktop perform like a new system.
Yes. The iMac is a desktop computer with the display built into the chassis. We repair iMac screens, replace internal storage, diagnose logic board issues, and recover macOS installations. iMac repairs require Apple-specific expertise and careful handling of the bonded Retina display — our technicians are experienced with both Intel and Apple Silicon iMac models.
Yes. We source components based on your budget and needs, assemble the system, install Windows, test for stability, and hand you a ready-to-use custom PC. Whether you need a gaming rig, a video editing workstation, or a reliable home office desktop, we build it to your specifications.
No. Walk-ins are welcome during business hours. Desktop towers are larger than laptops, so please bring your tower unit only — you do not need to bring your monitor, keyboard, or mouse unless you suspect one of those is the issue. Call (703) 594-9339 or fill out our online quote form for a free estimate before your visit.
Ashburn, VA customers: We are just 10 minutes from Ashburn via Route 7. Ashburn repair pages coming soon.
