# OEM (stock) drives

> How freemkv works with a normal, off-the-shelf optical drive. Covers DVDs, the legitimate AACS handshake for Blu-ray and 4K UHD, and why stock drives can be slow ("rip-lock").

Source: https://freemkv.org/docs/drives-oem/

An **OEM drive** is just a normal drive: the one that came in your computer, or any Blu-ray/DVD drive you buy off the shelf. It runs the manufacturer's original ("stock") firmware. **Most people have one of these, and that's completely fine.**

## DVDs just work

DVDs use older copy protection that freemkv handles entirely on its own. **Any drive, no setup, no key files**: put the disc in and rip.

## Blu-ray and 4K UHD: the legitimate AACS workflow

Blu-ray and 4K UHD discs use a newer protection system called **AACS**. freemkv reads them the official, by-the-book way, the same handshake the AACS system was designed for. Two things have to be in place:

1. **A security handshake with the drive.** Before it hands over the disc, the drive checks that the software is allowed to ask, using a *host certificate*. freemkv performs this standard AACS handshake; nothing is bypassed or faked.
2. **Credentials, from your key sources.** freemkv reads its host certificate and the disc's keys from the **[key sources](https://freemkv.org/docs/decryption-keys/)** you set up: a local key database or an online key service. That's why a disc that "just works" in some other software needs this one setup step here: freemkv keeps these credentials in *your* key sources instead of baking them in.

DVDs need none of this; Blu-ray and 4K UHD do. See **[Decryption Keys](https://freemkv.org/docs/decryption-keys/)** to set up your key sources.

> **Caution: On a stock drive, AACS is only as good as your key source**
>
> freemkv doesn't bundle host certificates or disc keys; on a stock drive it can **only** use what your configured key sources actually provide. If the host certificate, or a particular disc's keys, aren't in your key source, that disc won't decrypt on a stock drive. That coverage can be **limited, or for some discs not available at all**. This is one of the things an **[unlocked drive](https://freemkv.org/docs/drives-unlocked/)** solves: it removes the host-certificate requirement entirely.

## "Rip-lock": why a stock drive can be slow

Many manufacturers **rip-lock** their drives: the firmware deliberately caps the read speed when it notices you're copying a whole disc (it keeps the drive quiet and cool for movie *playback*). Nothing is broken; it's slow *by design*, and a two-hour movie can take a while.

If you want full speed and fewer restrictions, that's exactly what an **[unlocked drive](https://freemkv.org/docs/drives-unlocked/)** gives you.

## In short

| Disc | On a stock drive | Host cert + keys needed? |
|---|---|---|
| DVD | Works, any drive | No |
| Blu-ray | Works *if* your key source has the cert + keys | Yes |
| 4K UHD | Works *if* your key source has the cert + keys | Yes |

Want it faster, or is a particular drive giving you trouble? See **[Unlocked drives](https://freemkv.org/docs/drives-unlocked/)**.