Your motherboard has been running a second operating system this whole time, even when your PC is off

Published Aug 17, 2026, 4:30 PM EDT After a 7-year corporate stint, Tanveer found his love for writing and tech too much to resist. An MBA in Marketing and the owner of a PC building business, he writes on PC hardware, technology, and Windows. When not scouring the web for ideas, he can be found building PCs, watching anime, or playing Smash Karts on his RTX 3080 (sigh). No, I'm not talking about a dual-boot setup that you forgot about. Your PC executes a ton of code even before your main OS starts loading. The very first thing that fires up when you press the power button is a secret security processor that has scary levels of access to your machine. And it stays on even if you've turned your PC off, as long as the PSU is connected to the wall. Both Intel and AMD systems have had tiny subsystems embedded into the chipset (Intel) or the CPU (AMD) for years. These autonomous processors have their own firmware and enjoy low-level access to your machine. They execute core security and boot functions on your PC, but have come under the scanner for their closed-source code and security vulnerabilities. And you've never seen it in action Many of you might be surprised to know that, since 2008, Intel systems have had an autonomous subsystem called the Intel Management Engine (ME) integrated into the motherboard chipset. In the AMD camp, the Platform Security Processor (PSP) has been part of the CPU die itself since 2013. Both of these security processors have their own OS with direct access to the system memory and even the network adapter (in the case of Intel ME). As long as your PC receives a trickle of power from the wall, these subsystems can continue to run in a low-power state. They're powered by small microcontrollers built on an Arm, Quark, or ARC core. The level of system privilege they enjoy is the most surprising part of the story. They sit above the main OS and the hypervisor (if enabled), enjoying Ring -3 (minus 3) access to your machine. At this level, the Intel ME or AMD PSP can execute any code that is impossible to detect. This is what alarms security researchers, prompting them to raise concerns about potential misuse. It exists for a reason, but it's also kind of a backdoor What you don't know can hurt you The reason Intel ME or AMD PSP enjoy such heightened system access makes sense. IT admins need remote management access to troubleshoot and update thousands of machines even when they're "off." These subsystems load even before the main x86 cores of your PC and ensure that the system firmware and crucial hardware components are ready before the main OS starts booting. Hardware-level security, fTPM, and other security features are also handled by Intel ME/AMD PSP. The complicated part of the story is that both Intel ME and AMD PSP have a documented history of security flaws allowing attackers complete and undetected access to the system. Intel ME is especially prone to remote network exploits due to its independent network stack, which isn't present on PSP. Researchers have continued to discover vulnerabilities as recently as this year, including cryptographic key leaks and access to the System Management Mode (SMM). Secure Boot bypass, bootkit attacks, and many other vulnerabilities were discovered and patched with UEFI updates, but the fact is that you still don't have complete low-level control of your machine. It's impossible to audit the closed-source code of Intel ME or AMD PSP, and Intel and AMD have repeatedly refused to make it public, citing security and intellectual property concerns. You're essentially trusting your CPU manufacturer to keep your machine secure. You can't disable it completely, and you shouldn't try anyway The payoff is usually not worth it Although you might be able to turn some features of Intel ME or AMD PSP off in the firmware, you can't disable these subsystems completely. They're fundamental parts of your machine, and trying to disable them forcefully using tools like "me_cleaner" can brick your motherboard, leaving you with an unbootable PC. Whether you like it or not, Intel ME/AMD PSP is required to initialize the main x86 cores of your CPU and manage core boot functionality, so you can't get rid of them. Although you can consider laptops from niche vendors like Purism that come with neutralized ME functionality, most people should not bother. The realistic attack surface for an individual user is small, and Intel ME/AMD PSP serves essential use cases for enterprises. You can do your part by keeping your PC's firmware updated and Secure Boot enabled. Modern computing is more complex than the average user realizes Whatever your opinion about subsystems like Intel ME and AMD PSP, there's no denying that modern PCs have become quite complex. When you press the power button, millions of lines of code are executed even before you see anything on the screen. Security vulnerabilities will always exist, but manufacturers will also keep up with security patches to tackle them.