XBOX-360 SPECS - Updated 9/24/08

These tech specs are a complete (as possible) in-depth, and detailed look, at the Xbox360 System.

Hardware Specs:

Custom IBM Power-PC Based CPU (Xenon) 90nm Process (65nm In 2007) (45nm In 2008?)

    * The package is a 2-2-2 FC-PBGA, measuring 31mm by 31mm
    * 168 mm2 die size; one cpu core is about 28mm2
    * Support logic for Array and Logic Built in Selftest
    * 165 Million transistors
    * Three symmetrical cores running at 3.2 GHz each = 9.6Ghz throughput.
       > 32 KiB of L1 instruction cache and 32 KiB of L1 data cache per core
       > 64 bit CPU cores based on the IBM 970 "G5" design
       > Each core is two way SMT-capable and clocked at 3.2Ghz
       > 2× (128×128 bit) register files for each core
       > Two hardware threads per core; six hardware threads total
       > VMX-128 vector unit per core; three total
       > 128 VMX-128 registers per hardware thread
    * 1 MB L2 cache
       > (lockable by the GPU) running at half-speed (1.6 GHz) with a 256-bit bus
       > 51.2 gigabytes per second of L2 memory bandwidth (256 bit × 1600 MHz)
    * 21.6 GB/s front side bus (aggregated 10.8 GB/s upstream and downstream)
    * 115 GFLOPS theoretical peak performance
    * CPU Integer Perf (VPR): 1089 (363 each)
    * Dot product performance: 9.6 billion per second
    * IBM eFuse technology
    * IBM's PowerPC instruction set architecture
    * Restricted to In-order code execution
    * Big endian architecture

Bandwidth for Intelligent Memory is derived from the following events occurring every cycle:

2 Quads of samples/cycle * 4 samples * (4 bytes color + 4 bytes Z)*2 (read and write)*500mhz =3D 256 gbytes/sec (that is, 2 Terabits/sec).

CPU Game Math Performance

    * 9 billion dot product operations per second
    * 48 ALU ops * 5 floats (ATI vector5s) * 500(Mhz) * 2 (MADD) = 240 Gflops (11.2 more than PS3) for Xenon, and Xenos as a team.

GPU - Custom ATI (Xenos) ATI R500 based Graphics Processor (90nm Process - 65nm by 2010?)
     
    * 325 Million transistors (235m Parent Die / 90m Daughter Die) (Other specs say 337 million total)
    * GPU & Northbridge (Northbridge on Parent Die)
    * Two-die design, with two chips in a single package on a single substrate
       > Parent die contains the GPU and memory controller
       > Daughter die consists of the 10MB of eDRAM & additional logic (FSAA, Alpha, ZLogic & Stencil)
       > 2GHz link between the parent and daughter die
    * 500MHz processor
    * 10 MB of embedded DRAM (By NEC)
    * 48-way parallel floating-point dynamically scheduled shader pipelines
       > 4 ALU's per pipe for Vertex or Pixel Shader processing
    * Unified shader architecture (Beyond Shader Model 3.0)
    * Three SIMD engines with 16 processors per unit (The 48 shader pipeline) 
    * 16 Filtered & 16 unfiltered texture samples per clock
    * HDR Rendering
    * DirectX 9
    * Limited support for DirectX 10
    * Handles all scaling of video (resolution).

Rendering Performance: This logic is made up of 192 component processors capable of doing the basic math necessary for multi-sampled anti-aliasing.

GPU to Daughter Die Interface
    * 8 Pixel/Clk
      > 32BPP Color
      > 4 Samples Z - lossless compression
    * 16 Pizel/Clk - Double Z
      > 4 Samples Z - lossless compression

Alpha & ZLogic to EDRAM interface
    * 256GB/s
    * 32 samples x 32-bit color, 24-bit Z, 8-Bit stencil
    * Double Z
      > 64 samples x 32-bit color, 8-bit stencil

Polygon Performance

    * 500 million triangles per second

Pixel Fill Rate

    * 16 gigasamples per second fill rate using 4x MSAA

Shader Performance

    * 48 billion shader operations per second (other specs say 96 billion shader operations per second)
       > 4 Shader operations per pipeline per cycle
       > 192 Shader operations per cycle across the entire shader array

Southbridge

    * Enables all of the Ethernet and controller issues, and TV encoder (handles resolution, scan rates & inerlacing, and other TV related issues.)

ANA

    * Video output chip (Analog) a means of transferring the framebuffer into all of the different signals: Composite, s-video, RGB SCART, component, and VGA.

HANA - HDMI Equipped Units

   * Video output chip (Analog / Digital) a means of transferring the framebuffer into all of the different signals: Composite, s-video, RGB SCART, component, VGA, and HDMI (Digital).


System Memory - Mainboard & GPU

    * 512 MB of GDDR3 RAM
    * 700 MHz DDR
    * Unified memory architecture (GPU & CPU Access)
    * 128-bit interface to ATI's memory controller

Memory Bandwidth
   
    * 32 GB/s GPU to eDRAM bandwidth
       > 2 GHz � 2 accesses per clock cycle on a 64 bit DDR bus
    * 22.4 GB/s memory interface bus bandwidth (low latency path to CPU cores)
       > 700 MHz � 2 accesses per clock cycle (one per edge) on a 128 bit bus
    * 256 GB/s memory bandwidth to EDRAM
    * 21.6 GB/s front-side bus

Overall System Floating Point Performance

    * 1 teraflop


Storage

    * Detachable and upgradeable 20GB hard drive (Premium)
    * 12x dual-layer DVD-ROM
       > Toshiba/Samsung
          > TS-H943
             > MS25, MS28
       > Hitachi/LG
          > GDR-3120L
             > 46DH, 47DG, 47DJ, 59DJ ,78FK, 79x
       > Benq/Phillips
          > VAD6038
       > LiteOn
          > DG-16D2S
          > No FlashROM
    * External USB HD-DVD Drive
       > SD-S802A
    * Memory Unit support starting at 64 MB
    * 512MB Memory Unit
    * 20GB Hard Drive (Premium - Ended September 2007)
    * 60GB Hard Drive (Premium - Started September 2008)
    * 120GB hard drive (Elite Models + Seperate retail package)
    * USB Mass Storage Device (Not for gamesaves)


Southbridge (Developed by SiS)

    * The South Bridge is responsible for communication with the audio codec, storage devices, USB ports, controllers, and any other I/O devices.


I/O

SiS Customized Multimedia Chipset

    * Compatible with PCI Express technology
    * Two independent Serial ATA ports
    * Three USB2.0 high-speed ports
    * One 10/100Mbps Ethernet port
    * SATA Hot-plug function

Ports

    * Serial ATA
       >150MB/s data transmission rate
    * Support for up to four wireless game controllers
       > Proprietary 2.4Ghz wireless technology
    * Support for four wired game controllers
       > Front two USB connectors
          > Use HUB for two additional controllers
    * Three USB 2.0 High-Speed ports (Two Front / One Rear)
    * Two memory unit slots (Front)
       > Similar to a USB Port except it has 3.3V supply, and two grounds
    * Ethernet Port (RJ45)
      > MII interface
      > 10/100Mbps


Optimized for Online

    * Instant, out-of-the-box access to Xbox Live features with broadband service, including Xbox Live Marketplace for downloadable content, gamer profile for digital identity, and voice chat to talk to friends while playing games, watching movies, or listening to music
    * Built-in Ethernet port
    * Wi-Fi ready: 802.11a, 802.11b, and 802.11g (With USB Adapter - WiFi not built in)
    * Video camera ready

Digital Media Support

    * Support for HD-DVD, DVD-Video, DVD-ROM, DVD-R/RW, DVD+R/RW, CD-DA, CD-ROM, CD-R, CD-RW, WMA CD, MP3 CD, JPEG Photo CD
    * Ability to stream media from portable music devices, digital cameras and Windows XP-based PCs
    * Ability to rip music to the Xbox 360 hard drive
    * Custom playlists in every game
    * Built-in Media Center Extender for Windows XP Media Center Edition 2005
    * Interactive, full-screen 3-D visualizers

High-Definition Game Support

    * All games supported at 16:9, 720p, 1080i, and 1080p anti-aliasing.
    * Standard-definition and high-definition video output supported

Audio Capability

    * Multi-channel surround sound output
    * Supports 48KHz 16-bit audio
    * 320 independent decompression channels
    * 32-bit audio processing
    * Over 256 audio channels

Video Output

    * Composite RCA
    * Component (Analog RCA)
    * VGA (Analog - 15 Pin)
    * PAL - RGB SCART (PAL Region)
    * HDMI v1.2a (Premium Systems Made Since July '07, Elite, & H3 Editions)

Audio Output

    * RCA (R/L) + Dolby ProLogic
    * Optical = DD5.1

System Orientation

    * Stands vertically or horizontally

Customizable Face Plates

    * Interchangeable to personalize the console

Security Features:

Hypervisor

    * Microsoft protects the integrity of its system with a hypervisor. Using the virtualization technologies of today's processors, a hypervisor can act as a small piece of code with even higher privileges than the more complex operating system. In theory, even potential flaws in the operating system cannot be exploited since the hypervisor puts up additional restrictions.

In case of the Xbox 360, the hypervisor is responsible for encryption, decryption and the enforcement access restrictions on memory.

Thanks to the work (http://www.securityfocus.com/archive/1/ … 0/threaded) of an anonymous hacker, a flaw in the hypervisor has been discovered on certain versions of the Xbox 360 kernel, allowing the injection of code, which has not been cryptographically signed by Microsoft.

CPU

    * CPU Key (KeyVault) - Help to prevent modding
    * eFuse - Power Supply enable and eFuse Power Supply line
      > 12 'fuselines' of 64 fuses each
      > 5 'fuselines'  for about 320 fuses that can be used to prevent kernel downgrading
    * ROM storing Microsoft's Secure Bootloader
    * Console revocation table (for gamesaves) - Encrypted

eFuse (On Die - CPU) Technology: By utilizing an eFUSE (or more realistically, a number of individual eFUSEs), a chip manufacturer can allow for the circuits on a chip to change while it is in operation.  The primary application of this technology is to provide in-chip performance tuning. If certain sub-systems fail, or are taking too long to respond, or are consuming too much power, the chip can instantly change its behavior by 'blowing' an eFUSE. This process reportedly, does not physically destroy the eFUSE, so it is reversible, and repeatable.

New Xbox Owner: To prevent eFuse action; remove R36T, before hooking XB360 to internet.  Burned e-fuses prevent older firmwares (Kernels - currently any older rev. than 4552) from running on your Xbox 360, thus eliminating the possibility to downgrade to an earlier version of the kernel. The Resistor itself is located in the field T-6.  You can run your own code on Xbox 360 systems with kernel versions 4532 and 4548.

POWER SUPPLY

    * External Unit
    * 100 to 127 VAC Input @ 6.0 Amps / 47Hz - 63Hz (NTSC)
    * 200 to 240 VAC Input @ 2.7 Amps / 47Hz - 63Hz (PAL)
    * 12 / 5 VCD Outputs - 203 Watts
       > Three 12-VDC Sources @ 16.5 Amp Max
       > One 5-VDC Stb Source @ 1 Amp Max
          > Standby mode - Yearly power consumption of 17.52 kWh
    * Power/Error LED Indicator

GENERAL VIDEO DISPLAY INFORMATION Updated 10/10/2007

HDMI VIDEO - High-Definition Multimedia Interface: http://en.wikipedia.org/wiki/HDMI
The XB360 fully supports HDCP for both HD-DVD, and games apparently.  There is no real reason for HDCP to be active during game play, but Sony (for PS3) apparently decided to have it on during game play.  As far as I know, HDCP is not on during game play with Xbox360.


HDMI is an all-digital audio/video interface capable of transmitting uncompressed streams.  It supports all resolutions to, and including 1080p. 

HDMI to DVI adapter: Your DVI display MUST support HDCP.  Remember, the source is HDCP, and HDCP is active when using the HDMI port.

There is no significant difference in overall display quality over Component or VGA at 480i/p.  There is also no real major difference in quality in picture with a HDTV @ 32" and under, at any resolution. 

It is also said that you need only the best HDMI cable.  This is generally false in all runs under six feet.  A 12.00 cable will display just as good as the 60.00 cable at six feet.  What makes the cable cheap, or not so cheap is the shielding used to prevent interference from other signals, be it EMI, or RFI. In order to corrupt a digital stream, the interference must be strong enough to interrupt or drown out the digital signal.  With Analog signals, even the slightest bit of interference can show up on the display as a flaw.  The strength of the digital signal can fluctuate, but still display without any change in brightness or color, as the 1s and 0s contain all that information. So no matter how strong or weak (to a certain point) the digital signal is, the display remains the same.  That is the idea behind digital data.  The weaker an analog signal gets, the fuzzier, or lower in brightness/contrast the picture becomes.  The digital picture data contains a continuous information that tells the display how bright and colorful to be.  A very rough example would be, say your back is turned to me; I whisper "hello" to you in binary code, then I just say "hello" in binary code, only your ears heard the difference in the volume (say that is analog). However, your brain processed it as "hello" no matter what the volume of the numbers were (digital).

HDCP: http://en.wikipedia.org/wiki/HDCP
This protocol was designed so you could not record video from the HDMI port to any digital recording device.

Xbox360 Halo III Edition, Elite, and Premium consoles made in, and after the 3RD Quarter of 2007, will have an HDMI port.  These are the 2nd revision of the Xbox Mainboard called "Zeypher."  Jasper boards (V3.0) will also have HDMI.   The Xbox360 to date, uses HDMI V2.1 protocols.


COMPONENT VIDEO: http://en.wikipedia.org/wiki/Component_Video
Component video is an analog video signal that has been split into two or more components.  Typically colored red (Pr), green (Y), and blue (Pb).  Component video supports all resolutions to, and including 1080p.  You must have a HDTV that supports 1080p.

Component video does not contain HDCP Protocols.

Converting Component (analog) to HDMI (digital) requires an adapter that converts Digital to Analog, and they cost more than are worth.

The original XBOX360, Rev 1.0 boards, will use Component connections for HD Video. 

DVI VIDEO: http://en.wikipedia.org/wiki/DVI
Digital Visual Interface (DVI) is a video interface standard designed to maximize the visual quality of digital display devices such as flat panel LCD computer displays, and digital projectors.


One step up from Component and VGA, Both DIGITAL and ANALOG signals can be carried over DVI, with max resolution of 1080p both Digital and Analog. 

DVI does carry HDCP when using any HDMI adapter on either side of the cable.  There are known problems with HDCP; the display won't show a picture above 480p when DHCP is not working properly.  This is usually because the wrong adapter end for DVI was used.  You need what is called a DUAL LINK adapter.


If you have an Xbox360 with HDMI, and need DVI; You will need a HDMI to DVI adapter or cable, and it must be a Dual Link end for DVI.

VGA VIDEO: http://en.wikipedia.org/wiki/VGA
VGA is not a digital signal, and contains analog video only. 


You can easily adapt your component wires to a VGA plug, the video signals are analog either way.

VGA does not contain HDCP.

This is the type of connector to use XBox360 with a PC monitor, or other TV with this interface.  The resolution will only be as high as the monitor supports.

S-VIDEO: http://en.wikipedia.org/wiki/Svideo
Separate video, abbreviated S-Video and also known as Y/C (or erroneously, S-VHS and "super video") is an analog video signal that carries the video data as two separate signals (brightness and color)


S-VIDEO does not contain HDCP

There is an S-Video adapter for Xbox360.
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PROGRESSIVE AND INTERLACED VIDEO: Please read this information carefully.
http://en.wikipedia.org/wiki/Progressive_scan
http://en.wikipedia.org/wiki/Interlaced_video

TVs that do not display Interlaced Video, are deinterlaced, and shown as Progressive are:
LCD - DLP - PLASMA - Basically all non CRT (Cathode Ray Tube) displays. 

This means, your 1024(h)x768(v) LCD, DLP, or PLASMA TV, will show 480i, at 480p, 720i, at 720p, and 1080i at 768p, or the maximum (v)Vertical resolution.  The TVs will accept the "Interlaced" signal, they are converted to Progressive.  IF you had a 1080p LCD, you would also get 1080i at very close to, or at 1080p.

A CRT TV/DISPLAY is capable of displaying both Interlaced and Progressive Video.  These types of displays are: Computer Monitors - Single CRT HDTV - Three CRT Projection HDTVs.  See:
http://en.wikipedia.org/wiki/Cathode_ray_tube
http://en.wikipedia.org/wiki/CRT_projector

Newer SDTVs are being made with Component inputs, and are capable of 480p only.

eFuse Technology:

The technology of eFuses is not new, they were the basis of old one time programmable rom chips (OTP-ROMs or PROMs), the predecessors of today's eproms, eeproms, and flash chips. You could write these chips once once, by burning out bits with the writing voltage. When you were done with the programming, you could burn the write enable fuse and make the otp-rom a true rom. Until the write enable bit was burned you could erase the memory by burning all fuses of an already written address. (either to all zeros or all ones depending on the design, meaning that it is reversible). This technology is still in use in micro-controllers with one time programmable memory, but slowly gets pushed out by cheap flash based ones. But even some flash based ones have a write disable bit in their configuration range, that allows full write or even external read protection. The technology is good enough to be used as memory but the size of a classical eFuse comes from the 20 year old process that was first employed them, so they are quite large compared to today's transistor sizes. The programming is usually done with a serial programming interface and once completed, it can not be undone.

They are used on today's intel cpus to disable certain features, lock clock frequencies (no overclocking) and allow higher yields by allowing redundancy in certain circuits. On the normal ibm power cores, they are used to disable broken cache lines and activate the reserved backup lines. They can be used to deactivate certain computing elements too, and to allow for a microcode patch. The ibm cell cpu has 8 i/o processors but only 7 of them are active. One is a manufacturing reserve, so if one of the 7 cores blow during manufacturing they can use the reserve one and still sell the cpu as a fully working one.

Another use for efuses is the secure storage of serial numbers, and enrcyption keys. Once programmed the only way to read them would be to cut the chip, and use an electron microscope to scan them in. This was reportedly done by some eastern European nations during the cold war.

A public/private keypair is unique for every cpu, and the public part of the manufacturer key so they can issue bulk software. According to the ibm documentation, there is a possibility that some parts of the cpu cache are never swapped out. The graphic chip reportedly uses this area for communication with the cpu. The so called hypervisor can reside in this memory area too. During the boot process, the cpu reads in a flash chip and decrypts it's contents with it's private key. The chip is encrypted with the cpu's public key, so only the cpu could read it. All normal memory contents that gets swapped out of the cpu's l2 cache into the system memory will also get encrypted with the same key or some faster symmetric block ciper based on the private key. The os that later gets loaded into the system can't decrypt data signed by the manufacturer. For this it has to ask the hypervisor. So the encryption is double, everything in ram is encrypted by the cpu key and every data that is on an inport media is encrypted by the manufacturer key. The os can't break the cpu key since it never sees it and can't break the manufacturer key, because the hypervisor never let's the os touch it. The hypervisor can even check the os and even every data file for consistency and refuse to boot it if it's not signed with the right key.

Originally downgrading kernel was possible but Microsoft blew eFuses during the upgrade from kernel 4548 to 4552 as that's where they fixed the Hypervisor Vulnerability (which only works on kernel 4532/4548 and allows to run unsigned code / linux). It was already known that by removing the r6t3 resistor from the motherboard before the upgrade you could prevent MS from blowing eFuses and thus still be able to downgrade from a 4552+ to pre-4552, but we don't know how safe this is for future kernel updates.

MS doesn't blow new eFuses (located on the CPU dye) on each upgrade because they only have a limited amount available: 768 (12 'fuselines' of 64 fuses each) in total and only a part of these (5 'fuselines'(= 320 fuses)?) can be used to prevent kernel downgrading (= 80 possible downgrade bans? - once blown it can't be undone}. The eFuses also contain other data like a unique 'CPU Key'.

According to tmbinc, this key is used for:
* Encryption of the *keyvault* (that stores: console certificate(s), per-box private keys, DVD key, however NOT any code-related encryption keys)
* Encryption of an imported console revocation table (CRLL, that stuff which recently hit 360gamesaves.com, and no, this isn't live-related),
* "Encryption" of the pairing information of the 'CB' and 'CF' (for exact details, please reverse that code, it's a bit hard to describe.)

'CB' (2nd bootloader?) and 'CF' (kernel patches) are located on the Xbox 360 on-board flash in the "CPU data" section (data which is read when the power is switched on. If invalid, console might blink red etc.).

Quoting tmbinc and TheSpecialist:

All which is different from pre-4552 to 4552 and up are the G/H bits [part of eFuses]. They encode a "sequence" number, which is also stored in the CF "pairing" data, and one bit here is burnt to "increment" the sequence.
That means: If you know how to calculate the CF pairing data, you could modify the "expected sequence" value there (this, however, should be verified by someone.) And to be able to calculate that data, you need the "per-box-key". But if you have that, you could set the number of a 4532 to those of a 4552, and it should boot again.

At byte 0x21F in CF is the number that is incremented when a fuse is burned (thanks to Robinsod). This byte and ONLY this byte causes that you can't downgrade. We wanted to try to decrement that number again, but I just found that that's not possible without knowing the fuse data: byte 0x0 to 0x220 in CF are hashed (hash stored at 0x220). The hash routine uses the cpu key as input and verifies the calculated hash to the one stored at 0x220. So no downgrading without CPU key ...

So the 'sad' part is that you need this CPU Key if you wanna downgrade to a pre-4552 kernel ... and on kernel 4552+ there's no known way to get this key (yet). On kernel 4532/4548 you can use the Hypervisor Exploit to retrieve this data (like the Xell Linux Loader does) - but if you have one of these kernels you can already run unsigned code. However, if you're still on 4532/4548 this new hack will allow you to retrieve your unique CPU key, upgrade to a newer kernel and you'll be able to downgrade back to a pre-4552 kernel again even if eFuses got burned.

Robinsod tested this out successfully:

In the decrypted CF there is a "version lockdown counter" at 0x21F. Every time an update is applied (since version 4532) an eFuse is blown and the counter is incremented by 1 before it is written into the new CF. When booting, a check is made to ensure that the lockdown counter in the selected CF >= number of blown eFuses.
The good news is that we can modify the lockdown counter byte and re-encrypt the CF section. The bad news is that a hash of the first 0x220 bytes requires the CPU Key. So as long as we know our CPU Key we can downgrade to a vulnerable kernel.

1) Brand new XBox with 1888 & 2241
The Version Lockdown Counter in my 2241 CF is 0
2) Applied 4532
The Version Lockdown Counter in my 4532 CF is 1
Also fuseset 07: f000000000000000
3) Applied 4552
The Version Lockdown Counter in my 4552 CF is 2. Confirmed that I cant downgrade to unpatched 4532 dump
4) Fixed up a dump of 4532 with CF Lockdown Counter = 2. Boots!
Now when I dump my fuse data
fuseset 07: ff00000000000000
A second fuse was blown by 4552

Robinsod also released v0.6 of his 360 Flash Dump Tool(info) that will allow you to fix the 'version lock' in pre-4552 kernels (again - only if you have your unique CPU key) so it'll boot even on a Xbox 360 with eFuses blown by the 4552 update.
What's new/fixed:
* (v0.5) Now decrypts and extracts the Key Vault. You will need your CPU Fuses as dumped by Xell. The CxKey.txt file has changed, you need to add a ',' and your CPU Fuse data
* (v0.6) This release supports downgrading if you know your CPU key. Right click on a CF section and choose "Fix Version Lock", enter the new lock down number, click ok & then click "Patch" and choose the directory/filename for your patched flash image. The file produced is all fixed up and ready to be flashed into your 360.

If anyone, somehow, manages to find a way to get the 'CPU Key' out of your Xbox 360, then it looks like it's "game over" for our friends at Microsoft.

XDVDFS - WHAT IS IT?

The Xbox DVD File System is similar to a standard DVD, except it is a completely reversed system.  In normal applications, data is read from the hub, out towards the edge - from where the data ends.  With Xbox, the disc is read from the data ends, in towards the hub.  The drives servo (head) is wired reverse polarity, and the firmware is modified for it, along with the security protocols.   

Xbox original discs have three limitations:
- Outer space of the disc is not used. (space wasted)
- Xbox DVD video at the beginning of the disc (space wasted)
- And the most important: security place holders.

The original XBOX DVDFS is still the main building block factors with the Xbox360, all that changed was the offset where data begins -vs- the Xbox1 titles.  Still, with XB1 compatibility, the XB360 drives must be able to read both the XB1 and XB360 DVDFS.

Original XB File System: http://www.xbox-linux.org/docs/gdfs.html

Remember, the XB360 file system is similar, just the offset values changed.

The XB360 will launch XB360 titles from XB1 formatted discs, as an original.  Please refer to the Burger King games, where both the DEFAULT.XBE and DEFAULT.XEX, along with other files for BOTH consoles, that are present.  These discs (BK) are in XB1 format only, and can be viewed on a Modded XB1.  However, if you place an original "XB360 only" disc into a modded XB1, you get and see nothing.