PS2 [REQUEST] BIOS Patch for 128MB RAM and Region-Free Support

N

NinjahZ

Forum Noob
Hey everyone, I'm new to PSX-Place!

I'm open to criticism, thoughts, and ideas (don't get annoyed if I take them with a grain of salt).

I'm working on some ambitious modifications for my Ocean Blue Japanese Phat PS2 and would love to get some insights from this community.

Here's what I've done so far:
  • Replaced the two SDRAM modules in the PS2 to upgrade it to 128MB.
  • Testing has confirmed that the RAM is functioning correctly, but the PS2 is still detecting only 32MB due to the BIOS limitation.
My next step is to replace the BIOS chip with an aftermarket one for the mod, but I'm still researching which aftermarket BIOS chip would be best for this, I also plan to find a DMS4PRO Modchip to flash this BIOS.

What I'm hoping for:

I need help from someone who's patched the BIOS before, specifically modifying the RAM configuration to support 128MB instead of the default 32MB limit.

If possible, I'd also love to find a region-free BIOS that works alongside this patch to unlock full compatibility with games from all regions.

Has anyone here successfully patched the BIOS or can point me in the right direction for this? I'm particularly looking for anyone who's tackled the RAM configuration modification, as I know it's pretty uncommon.

Any help or guidance would be greatly appreciated. Looking forward to hearing your guys thoughts!
Thanks in advance!
 
First off All there IS no aftermarket BIOS for PS2. As the BIOS on PS2 IS not flasheable. All modchips including dms4, modbo just interupt the onboard BIOS on the fly for runing unsingned code and run backup games. It does not work like on ogxbox where the og BIOS IS not used at All.
What you need to do first IS to find compatible eeprom to replace the original nonflasheable on Board.
What chips have you used?

PS
Dont take it wrong,but as a new member as you are as just from today. Without proof it would be considered a hoax,because from what is in this group already written there are not pin to pin compatible ram chips on the marked with this bus width and kapacity.
 
Last edited:
Luisile said:
First off All there IS no aftermarked BIOS for PS2. As the BIOS on PS2 IS not flasheable. All modchips including dms4, modbo just interupt the onboard BIOS on the fly for runing unsingned code and run backup games. It does not work like on ogxbox where the og BIOS IS not used at All.
What you need to do first IS to find compatible eeprom to replace the original nonflasheable on Board.
What chips have you used?

PS
Dont take it wrong,but as a new member as you are as just from today. Without proof it would be considered a hoax,because from what is in this group already written there are not pin to pin compatible ram chips on the marked with this bus width and kapacity.
Click to expand...

Hey, well yes that's why I am here, because I need help and don't understand the software side of it, I have a background in repairing electronics so im just lucky I knew who to contact to find the right ram chips.

I ended up desoldering one of my ram chips and sending it away to find a compatible replacement, the company here in New Zealand gave me a call telling me they found original Toshiba PS2 Ram Chips!?, then they sent me back a Toshiba desktop ram module which I removed the heatspreader and desoldered the 2 ramchips (64MB Ea) then I resoldered them to the PS2 Motherboard, other than this, the only change ive made to this PS2 is the PSU, I swapped it out for from my old console (230V PAL)

I just found MechaPWN, the dev kits had 128MB ram, so if I do that to a 50000 series PS2 and it thinks its a devkit, it wont have them limitations hopefully, means i need a new ps2 board though

also if you know someone with the PS2 TOOL, they also use the same ram chips, however they run 128MB too, so possibly you could find exact part numbers.
 
Last edited by a moderator:
Mechacon or mechapwn has nothing to do with ram. Ram is chonnected directly to the main SoC. Either there is the limitation, what i believe it is or the bios.
 
Luisile said:
Mechacon or mechapwn has nothing to do with ram. Ram is chonnected directly to the main SoC. Either there is the limitation, what i believe it is or the bios.
Click to expand...
Mechapwn sets a retail PS2 as a devkit with custom firmware and spoofs the modelnumber, if my thoughts are correct I believe it would remove the limitation on RAM as devkits do have 128MB, I need to re do this mod on a 50000 series and test, I will come back when I do this with my findings
 
NinjahZ said:
Mechapwn sets a retail PS2 as a devkit with custom firmware and spoofs the modelnumber, if my thoughts are correct I believe it would remove the limitation on RAM as devkits do have 128MB, I need to re do this mod on a 50000 series and test, I will come back when I do this with my findings
Click to expand...
If you have the resources to do it then make it and post results here. I will wait for it
 
NinjahZ said:
Mechapwn sets a retail PS2 as a devkit with custom firmware and spoofs the modelnumber, if my thoughts are correct I believe it would remove the limitation on RAM as devkits do have 128MB, I need to re do this mod on a 50000 series and test, I will come back when I do this with my findings
Click to expand...
For the records mechapwn changes console behaviour not to the devkit (Development Kit) but to the debkit (Debug Kit). Debug Kit has almost the same hardware as retail models, only mechacon, dsp and roms are different.
 
NinjahZ said:
I ended up desoldering one of my ram chips and sending it away to find a compatible replacement, the company here in New Zealand gave me a call telling me they found original Toshiba PS2 Ram Chips!?, then they sent me back a Toshiba desktop ram module which I removed the heatspreader and desoldered the 2 ramchips (64MB Ea) then I resoldered them to the PS2 Motherboard, other than this, the only change ive made to this PS2 is the PSU, I swapped it out for from my old console (230V PAL)
Click to expand...

Can you please give the model number of the toshiba desktop ram and some photos of your PS2 motherboard with the chips.
 
You must log in or register to reply here.

Similar threads

Back
Top