Project HoRizen GTXbox - Worlds most versatile Xbox Original

Mortis Angelus

Airflow Optimizer
Original poster
Jun 22, 2017
I have finally reached the state in my project of converting an original Xbox into a mITX PC that I am confident enough to start showing off a build log! In this first post I will show some images of which state I am in now, and also tell the background for the project and my personal criteria in what I want to achieve and how I think my Xbox will differ from all the previous Xbox-builds that have been done before. After that, I will, in various posts, share guides to how I solved some issues and designed my mounting-components. I hope you will enjoy the blog.

WARNING! You are about to enter A WALL of text! XD

Project HoRyzen GTXbox

Table of Contents:

1.1 Background - From idea to paper (Page 1)
1.2 Background - How to be special in a sea of Xbox-builds? (Page 1)
1.3 Background - Challenges I expected as I have no actual skills: (Page 1)

Current State of the build-sections:
The current state of the build (04 Jan 2018) (page 1)
The current state of the build (05 Jan 2018) (Page 1)


1.1 Background - From idea to paper:

The idea for this project popped up in my mind about 2.5 years ago while I was doing some retro-gaming on my Xbox original. I had just reached the point in my PC-enthusiasm that I thought I could take on such a challenge. Prior to this, I had only assembled my first computer (the previous gaming rig had been assembled by the store), so one thinks it is quite the jump to start making my own case. But in my humble opinion, building a computer these days ain't that much of a challenge. It is more or less building with larger Lego. But I digress. I just thought it would be a much more creative and more challenging task to build an mITX PC into an original XBOX.

So without even looking if anyone had done this before (quite frankly I didn't care and I wanted to go my own way) I began reading up on standard measurements, looking up potential parts and both eye-balling and looking at actual specification-graphs on components and went to the drawing table where I created the first crude drawing of a potential layout. Then I did some refinement and redrew my planned layout, which ended up looking like this:

While the current build deviates a bit from this original drawing, the main idea and layout is still the same. But gone is the single slot GPU (replaced with a half-height, dual-slot GPU instead), and 3x smaller fans on the right side and the 12.5 mm Optical Disk Drive has been swapped for a slimmer 9.5 mm one. But let's not get ahead of ourselves; this is still the background section.

1.2 Background - How to be special in a sea of xbox-builds?:

Even before looking up other similar builds I was certain of one thing: If one makes a sleeper xbox-PC the illusions must be as thorough as possible without any immediate giveaways. That means no super custom panels or mega-ventilation modifications, no changing of LED-light color, and MUST include an ODD! The system should also be completely modular to enable future re-builds and upgrade paths. But would this be enough to be special? And what do you know? After looking at other builds, I soon realized, I could actually manage to become a one-of-a-kind build. Here are links to a few builds I've looked at, both good and bad ones:

Xbox PC Build - a really good build and good video that gave a lot of ideas.

Xbox One Build - even though a different xbox, it is still inspirational. Also includes a GPU

OS Xbox Pro - Probably the best looking build, but is highly modified both inside and outside of the case.

Old PC in 360 - imo one of the worst atempts at this, but a good "don't do it like this"-video to watch.

The main thing I noticed with all of these builds, in particular with the otherwise good looking OS Xbox Pro-build, is that they all place the motherboard on the bottom of the case (for convenience) and then stack the storage drives or even the PSU ontop,which totally chokes the CPU-cooler and hinders any proper airflow.

Another thing is that everyone goes for an internal PSU-solution and skipping the ODD. Most also either heavily modify or completely remove the original heat-shield of the original xbox. I have seen fans and PSUs GLUED to the plastic shroud and many other (sorry for language) half-assed solutions that is just lazy imo. Not to mention; no upgradeability or possibiity for repair if anything breaks down.

So in the end, here are all of my personal criteria for this build; all the boxes that had to be ticked for my personal take on this concept:

1) Has to be able to do everything an Xbox does. That includes playing optical disks!

2) The build MUST be restrained within the original heat-sink. Not only is this a more fun challenge, it also makes it easier to plan, and there are now much more proper mounting places for various components

3) Must use off-the shelf, standard components! This means standard ATX/ITX-components. That excludes MXM and STX components. This is for two reasons: A) MXM/STX are much harder to come by, much more expensive and not available everywhere to buy, and B) What is the challenge of a build, if you can just place a smaller MXM-based motherboard inside the xbox and call it a day? Then I could have just placed a NUC inside and be done with it. I think not!

4) Modularity! Everything must be able to be swapable. Nothing must be glued or in any other way permanently attached. This will allow for future modification and also enable upgrading of hardware as newer generations are constantly released.

5) Silence and highest possible airflow. I want a cool and silent, but efficient PC that still can perform. This means no placing of components above the motherboard, proper flow-paths and plenty of ventilation combined with silent components and fans. Original plan included 6 fans on low RPM, but has since been reduced to only 3 fans. :D

6) Should be able to game! Most xbox-builds puts a flex-PSU inside the case, a motherboard and uses the intergrated GPU and calls it a day. Not me. I want a dedicated GPU along with the ODD. HDPLEX-PSU with external power brick was a clear choice from the start (well.. at least as soon as I found out about the HDPLEX).

7) Incognito. Looking at the PC on a shelf or a table, it should not be evident immediately that it is not an Xbox. Keep the original green LEDs for the power button, only make some small ventilation holes on top between the original grooves, and change the Xbox-controller ports to USB-ports. The last one is easy to spot for a trained eye, but for most people, not so easy. Many people make their xbox builds have a blue or red light, which destroys any illusion. I DO NOT CARE ABOUT HOW IT LOOKS FROM THE BACK, because that obviously has to be heavily modified.

8) Should be a proper PC - that includes having proper storage. Again, most people just shove in a 2.5" drive and call it a day (remember, most builds were done when M.2 didn't exist). My build has room for 1x ODD, 4x 2.5" drive and 1-2x M.2 drives (depending on the mobo).

By fulfilling all of these criteria, I not only have a very unique build, but I believe (unless someone counters me) that it will be the most versatile Xbox ever built; it can do everything. Sure, there are builds with better GPU, but no ODD. There are those with a better CPU, but usually then no GPU or ODD (due to lack of power and thermal solution). And there are builds with less storage. There is also an expansion plan ready for this build where the GPU is upgraded to a Quadro P4000. This would, unfortunately, reduce the drive amount to only 2x 2.5" drives.

1.3 Background - Challenges I expected as I have no actual skills:

There were obviously lots of challenges I expected to meet along the way. Most obvious; where to find a broken Xbox (no, I wasn't going to tear down my own working Xbox), what components to use and what to compromise on. But the most important challenge would be the simple fact: I have no experience building a computer case, much less modifying another enclosure. I have no tools and no actual skills.

But none of these things scared me. In my childhood I was quite good in school at both wood working and metalcrafting, and my Dad is a seasoned metalworker. So saying I have no background is perhaps wrong, but I certainly have never done anything like this. But I know this: What I don't know, I can learn, and much of this kind of work, is not difficult per se, but is a game of patience and being nitpicky. And in the latter I am a master. So here I am now, 2.5 years after my initial plans, actually building and doing this project. And thanks to the welding and drilling skills of my Dad combined with my intense nitpicky planning and attention to detail, it really looks now like it will be finished (more or less) in a couple of days (written 04 Jan, 2018).

Another challenge has been the fact that I dont own my own workshop, so I can only build while visiting my parents. To make matters even more difficult, I moved abroad in March 2017, which limited my access to the workshop even more. So the actual building time has been a few days during summer 2017, and now during my three weeks of winter holiday in (dec 22 - Jan 10). In between I then collected components and tools required.


That was all I for now. Below is a brief look on how things look at the moment. I will from time to time now make blog posts on the designing and building during this project providing full disclosure and drawings for those who would like to mimic.


The current state of the build (04 Jan 2018):

Here comes a few images showing the current state of the build. Please note, that there is quite some work still to be done!

All the main components, save for the 2.5" drive tray(s) and the 9.5 mm optical disk drive (ODD), have been fit in. When this picture was taken, I am waiting for the glue holding the motherboard (mobo)-spacers to dry. This is not a permanent solution, but a temporary one, so I may drill holes and fasten the spacers properly with screws. More about this in a later blog. Components in picture: AsRock AB350 mITX Fatal1ty + Ryzen 5 1500X, Noctua NH-L9a, MSI GTX 1050 Ti LP OC, HDPLEX 300W, 3x 60x60x16 mm Gelid Silent 6 fans, Some generic USB3-ports (2 will be coupled to the USB2 header).

Perhaps not the best cut-out job ever made, but considering I have never done anything like this before, and last time I held a power tool was like 9 years ago (save for the cut-out grinding I did on the xbox-top part last summer), I am pretty happy with the result. Kudos to @Necere for providing the necessary information I needed to make the back I/O-shield cut-out!

Cable management is going to be the greatest challenge aside from designing and building the mobo-spacers. Here I am just test-attaching the front USB3-cable to its header. It is a pain in the buttox, but doable. The theoretical distance between the mobo and the HDPLEX on paper was 7 mm. The USB-cable is 5 mm thick. And reality is always a bit more cramped than in the drawings. But I shall prevail!


My Dad - For his support and his excellent metal working skills. This build would not have been possible without him.

Thomas B. - For teaching me basics about various computer and component related stuff, and for general mentoring in the beginning.

Jonas P. - For helping me with getting some material and for bending the 2.5" drive trays

Christiane & Andreas - for helping me import much cheaper PC-parts from Germany when international shipping wasn't available.

Robin H. -
For all the idea-throwing back and forth

@Necere - For aiding me with the back-IO-shield cutout design and placement

My girlfriend - For supporting this insane idea and giving a helping hand every now and then

This awesome community which is a constant inspiration, guide and help for builds like these! Thus I must also acknowledge @Josh | NFC who guided me here to SFF Forum in the first place and was my first main SFF build-inspiraton.
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Mortis Angelus

Airflow Optimizer
Original poster
Jun 22, 2017
Current state of the build (05 Jan 2018):

I am happy to report it is now all assembled:

All in all, I am extremely happy and satisfied with the build. I have only found 1 major issue (discussed in a spearate thread here - Please help me!) and 2 minor issues:

- The holder for the ODD is a bit too wide, and needs to be grinded down. Being too wide results in the ODD-tray to hit the plastic frame on the left side and thus hinders the ODD from opening. Of all the things that could have gone bad, I am happy it was this, because the ODD is on the top of everything, and easy to remove and fix! Yay! :p

- The coil whine is real! I'm not sure if it is the GPU or HDPLEX. It sure sounds like it comes from the GPU, but perhpas you pros can tell me.

A proper edited video with timelapse will be released sometimes in the following weeks.
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Mortis Angelus

Airflow Optimizer
Original poster
Jun 22, 2017
Current state of the build (29 March 2018):

It is FINALLY properly alive. All installed with Win10 and working without a hitch (jinx jinx). Now I'm approaching the 3-year mark for when I first begun planning this little beast.

As can be read in the posts above, I had some issues getting it up and running. But thanks to Larry over at HDPLEX I got the power issues fixed, and the startup issues was fixed with your (community) help! Thank you guys! I have also been waiting to update my desk setup, which has also prolonged the process of getting this machine up and running.

I have also now added a Crucial MX300 525 GB SSD along with the Seagate 2TB 5400 rpm SSHD. I will now (finally) start to write the full build log here, so that if anyone else wants to build something similar, they will be able to get measurements and desings (and inspiration) from this build.

Thanks again everyone!

Next out, I will have to betray you guys a bit; Planning a big custom water cooled system now with 8700K + 1080Ti inside of a Fractal Define R6.
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