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DARKSOFT How to convert a Xbox PCB to repair Chihiro

Darksoft

Darksoft

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Hello!

As many of you have noticed, then main reason why a Chihiro goes broken, are those damned fans over the heatsink on the GFX chip. previous versions had just a bigger heatsink that was enough to do the job.

As a result, the GFX chip breaks and you end up with a brick.

In order to fix your Chihiro, you can take a specific model of Xbox and modify it to work as a Chihiro PCB.

to convert a xbox mobo into a chihiro motherbase, you need to double the amount of ram memory that the xbox has. For that, you need to buy 4 of these:
https://www.ebay.es/itm/1-PCS-K4D26...700760?hash=item1c89a9f358:g:FaoAAOSwgv5ZU2Mc

See here for more info on the process:
http://www.gc-forever.com/forums/viewtopic.php?t=1060
If you are not an expert, I recommend that you ask @irepairsega who is an expert on this and knows how to do the job for a reasonable fee.

About the Xbox to be converted, check here:
http://www.informit.com/articles/article.aspx?p=367210&seqNum=2

You can only convert XBOX that have the chip Coneixant on the video Output and Bridge MCPX X3.
Those are the ones which have 1.3 or older. You can know the revision just by the serial number.

If serial number is 32 or smaller, you are good.

Once you have the right motherboard and the extra ram installed, you just need replace the 24C02 and the 29F080.

The 29F080 is the same always. The 24C02, you may want to change as that file specifies the MAC address the the motherboard will have.
http://www.mediafire.com/file/jriiv826bwmpghy/Chihiro_I2c%2BFlash.rar/file

The link includes 2 differen 24C02 files so you can see what changes. The CRC is calculated in the same way as it's done in the Chihiro, in case you want to change it. See here how to calculate it: http://xboxdevwiki.net/EEPROM

I heard that those 2 memories can be updated like in Xbox without desoldering. I never tried though. See here small tutorial in Spanish about changing the content without desoldering:
https://www.elotrolado.net/hilo_tutorial-como-leer-y-o-escribir-en-la-eeprom-via-hardware_879366

Enjoy!

Let me insist on this again. The process is complicated, so dont do it yourself unless you know what you are doing. I strongly recommend you to get in touch with @irepairsega to get one.

Thanks!
 
The number 32 is part of the serial#. There are hundreds of thousands of Xbox out there that are good.
 
why don't you give it a go and let yourself surprise?
 
whatnot said:
Removed
Click to expand...
This line doesn't make sense to me since the entire process is outlined here. It doesn't say you HAVE to send it to @irepairsega, only that desoldering/soldering those chips isn't easy for everyone.

If it said "@'irepairsega' offers this service, can't tell you any details" then sure, reason to be weirded out. But the only files/info you need are linked above, so you can look into it yourself.

There's nothing stopping you or I from following the instructions above.

I'd give it a shot just to be able to go "Hey, this works" or "No, it doesn't", but I don't have the rest of a Chihiro, so no real point as I wouldn't be able to tell if it worked or not anyway.
 
@whatnot I better understand what you're saying now.

I think I got thrown off with the initial "I would be very surprised if this actually worked".
 
back to topic please. Can anyone try and confirm?

Thanks.
 
funny how things work :) 1 picked up 2 semi-broken chihiro last week for peanuts :whistling: One is booting but resetting, the other one I get a black screen so far.

but please Darksoft, could you let me finish one project before giving me more work already ?! X/

I've also picked up a Namco system 246 so please hang on announcements on that side for a while ok?
 
I have a non working chihiro and the right extra xbox but not super confident that my skills are that good for this. Something for the future
 
You need the last 5 digits of the serial number. The first digit of that is the year the xbox was manufactured. The next 2 digits are the week in that year the xbox was manufactured. Everything 2001 and 2002 should be fine. First 8 weeks of 2003 might be fine as well.

Those early xbox boards have a 1 row AT style power connector. Chihiro type 3 boards usually have a dual row ATX style connector. So you might need another power cable between the base board and the main xbox board.

It's unclear if the bigger gpu heatsink without fan offers enough cooling. The xbox has the harddrive caddy that is shaped to direct the case fan airflow over the cpu and gpu heantsink. The chihiro isn't having this, but it's case fan is rotating full speed, so it's generating more airflow. Why did sega continue using the gpu fans when the original xbox had changed it's design? A passive cooling with a bigger heatsink is more reliable and cheaper. The gpu isn't having a temperature sensor. Maybe it's possible to compare temperature with an infrared thermometer?

Be carefull if you buy your ramchips on ebay. Some sell some strange items that are SAMAUNG instead of SAMSUNG.

They used to number xbox motherboard revisions with a number 1.x. 1.0 boards have a gpu fan and a small separate usb hub board. 1.1 boards have the bigger heatsink without the fan and don't have that usb hub board. 1.2 boards have the dual row ATX style power connector, but have a smaller flash chip (only 256KB instead of 1MB) 1.1 and 1.2 boards don't have a connector for the gpu fan. (The solder pads exist.)
 
Darksoft said:
Hello!

As many of you have noticed, then main reason why a Chihiro goes broken, are those damned fans over the heatsink on the GFX chip. previous versions had just a bigger heatsink that was enough to do the job.

As a result, the GFX chip breaks and you end up with a brick.

In order to fix your Chihiro, you can take a specific model of Xbox and modify it to work as a Chihiro PCB.

to convert a xbox mobo into a chihiro motherbase, you need to double the amount of ram memory that the xbox has. For that, you need to buy 4 of these:
https://www.ebay.es/itm/1-PCS-K4D26...700760?hash=item1c89a9f358:g:FaoAAOSwgv5ZU2Mc

See here for more info on the process:
http://www.gc-forever.com/forums/viewtopic.php?t=1060
If you are not an expert, I recommend that you ask @irepairsega who is an expert on this and knows how to do the job for a reasonable fee.

About the Xbox to be converted, check here:
http://www.informit.com/articles/article.aspx?p=367210&seqNum=2

You can only convert XBOX that have the chip Coneixant on the video Output and Bridge MCPX X3.
Those are the ones which have 1.3 or older. You can know the revision just by the serial number.

If serial number is 32 or smaller, you are good.

Once you have the right motherboard and the extra ram installed, you just need replace the 24C02 and the 29F080.

The 29F080 is the same always. The 24C02, you may want to change as that file specifies the MAC address the the motherboard will have.
http://www.mediafire.com/file/jriiv826bwmpghy/Chihiro_I2c%2BFlash.rar/file

The link includes 2 differen 24C02 files so you can see what changes. The CRC is calculated in the same way as it's done in the Chihiro, in case you want to change it. See here how to calculate it: http://xboxdevwiki.net/EEPROM

I heard that those 2 memories can be updated like in Xbox without desoldering. I never tried though. See here small tutorial in Spanish about changing the content without desoldering:
https://www.elotrolado.net/hilo_tutorial-como-leer-y-o-escribir-en-la-eeprom-via-hardware_879366

Enjoy!

Let me insist on this again. The process is complicated, so dont do it yourself unless you know what you are doing. I strongly recommend you to get in touch with @irepairsega to get one.

Thanks!
Click to expand...
Excellent work as always DS. Hopefully this will save a few more of the board from the bin
 
Good luck to anyone attempting this! Upgrading my Xbox to 128MB was the first quarantine mod that I completed.
I harvested the RAM chips from a V1.6. The XBlast OS 128MB RAM test was very helpful too.

It would've been a lot less annoying if it was only 1 chip to solder, but there are 4 in total! :thumbsup:

 
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