Chipped PAL PS2 outputs NTSC PS1 games in a slightly off refreshrate (Hz)

As the topic says a chipped PAL PS2 will output NTSC PS1 games at a slightly off refreshrate (59.40Hz), which causes stuttering when displaying the video through a XRGB-mini. This only happens with PS1 games though. All NTSC PS2 games are running at 59.82Hz which is still a bit off compared to the 59.94Hz which is the standard. Even though there is this slight difference the picture is perfectly smooth with zero stuttering.

This problem has been discussed in the XRGB-mini thread on shmups forum a few times already. And people with NTSC consoles say that their PS1 games are running perfectly smooth on their PS2s. I'm guessing they are also output in 59.82Hz like the PS2 games on mine, but I'm not sure.

Does anyone know if it's possible to boot a NTSC PS1 game on a PAL PS2 and possibly have it output in a different refreshrate? I've been looking into PSBBN, but I don't have any blank DVD-Rs so I haven't been able to try that yet. I'm thinking that since this is a Japanese OS it may boot a PS1 game like a NTSC console

Anyone have any other ideas? Besides me buying a US or JAP console/motherboard Also I should say that I only have interest in booting original PS1 games, no backups.

Here is a few pictures of the status screen on the XRGB when playing PS1 and PS2 games.

PS1 - Biohazard Gun Survivor (JAP):
http://i40.photobucket.com/albums/e...l stuff/IMG_0983_zps57ea06fd.jpg?t=1371320639
PS2 - Dodonpachi Dai-oh-jou (JAP):
http://i40.photobucket.com/albums/e...l stuff/IMG_0979_zps763c00c4.jpg?t=1371320612

 

What chip are you using?

Some Modcips use patches to do whats called a PS1 screen fix, I dont know if that will alter the frame rate at all but maybe its interfering in some way.

You can disable it on:
Matrix Infinity
DMS 3/4
Some Matrix clones (4 & 760)

It might be completely unrelated but worth a try.

 

Not a bad idea. My chip is a modbo 760 so it can be disabled. When I do this the image placed too far at the top, and the refreshrate says 49.75Hz and it says 288p resolution. So without PS1 screen fix it's outputting in 50Hz instead.

 

Doesn't sound normal. I thought PS1 games set the video mode in software, hence no such thing as a traditional 50hz/60hz switch for it.

 

I know what you mean. Unchecking the PS1 screenfix will place the image too high on the screen and cut off the top of it. It will output in 288p which is the PAL resolution. For some reason this is normal for chipped PS2's without the PS1 screen fix option. I used to have a PStwo with a Crystal -something- chip and it did not have PS1 fix and all import PS1 games were unplayable. Perhaps the fix is not 100% perfect, hence the reason we end up with a strange refresh-rate that causes stuttering in some video processors, and perhaps (and probably) on some TV screens too.

 

I doubt NTSC PS2's do that, but easy enough for me to burn a PAL PS1 game sometime. Barring laziness.

I've got XRGB-mini and chipped American PS2.

 

On the modbo 760 have you tried forcing the output to ntsc, instead of auto, or disabling the colour fix completley. This might not effect psx mode but its worth a shot.

 

So under Special > Full Status what does your XRGB-mini say when playing a NTSC PS1 game?

That only applies for PS2 games. But I have tried and it made no difference

 

Bump

 

My PAL fat and slim PS2s, both chipped with dms4 pro modchips also give the slightly off refreshrate (59.40Hz) that you mentioned when playing NTSC PS1 games.

When connected to the DVDO Edge though, it jumps between 59.37Hz and 59.45Hz.

I doubt that it would be somehow caused by the modchip forcing the wrong refresh rate as we both have totally different modchips. More likely caused by hardware differences between PAL and NTSC PS2s but that is just a guess to be honest.

 

I guess it'll have to wait. For some reason I'm not getting audio and video from component on this PS2 with the XRGB right now.
Eventually get around to trying different cables, directly to the TV, or whatever else.

 

Fair enough

 

A guy on a Danish forum got a JAP PS2 and tested it with the XRGB-mini:

PS1: 59.82
PS2: 59.93

So that will run stutter-free for sure. Now I just need to find me a JAP or US 5000X console or just the motherboard

 

If you get the SCPH-5000X series it is recommended that when using a modchip to do the romeo mod. http://sksapps.com/index.php?page=diagrams/ps2/laserfix.html Version 9 is GH-023 motherboard revision and V10 is GH-026 may also be a GH-029? Easy way to tell is from date code: 3A, 3B, 3C are v9s and date codes 3D, 4A are v10s maybe date code 4B through D but the others are confirmed.

I actually completed the romeo mod on my SCPH-50001 console and boots everything fine, if you want an example its at https://www.dropbox.com/sh/4qdw4s4xl1w8iny/ofaFhl4GCM under PS2 v9 Success, if you need replacement fuse locations I also have those from psx-scene.

Good luck if you do the mod,
HaloSlayer255

 

Nice of you to let me know. But I already installed a modchip along with the romeo mod in my 50004, so no worries

I'm just looking for a US or JAP version of the same model, as I have several loose drives for them in my basement

 

I just got hold of a US NTSC v12 PSTwo and I am also getting the same refresh rates as you posted above. I also noticed that the mini actually detects it as 240p when playing PS1 games rather than 241p which I get when using my PAL PS1/2 with the mini.

I've also compared the NTSC v12 motherboard with the same revision PAL motherboard and can't find any difference. All the crystals/oscillators on the boards are the same values and I'm not sure which is the clock IC but all ICs seem to match anyway so which ever one it is it must be the same on the NTSC and PAL board. Right now apart from the BIOS difference I really can't see what else is different from one board to the other that would cause the difference in refresh rates but I'm no expert so maybe I am missing something.

 

Great info. Perhaps Bad_ad could burn me a US bios that fits my 50004?

 

Maybe, but there wouldnt be a direct replacement. IIRC the ps2 bios is finer pitch than anything I could order.

So either "spider wire" the chip in, soldering each leg to each pad. Or get a faulty board and swap the bios

 

I had hoped it was a fairly normal chip that was easy to replace. Spider wiring should be easy enough though, the solder pads are pretty big if I remember correctly If you do decide to buy some I'm up for one, but who else would be anal enough about refresh-rates to want this besides me? Unless someone makes a cool something-BIOS mod I doubt there's a market for this

 

I think I might have some appropriate chips already, so buying them in for this specific purpose shouldnt be an issue. I will check when I am home.