PAL Sega Saturn crashes after 5 mins

So i got a Saturn off a friend years ago and forgot about it. Can't remember if it worked or not but.
After being in the loafed for about 10 years i decided to dig it out and put a 60Hz mod on it.

Before doing that i wanted to see if it actually work and it did for 5-10 minutes of me playing Sega Rally but when i turned it off to try a different game i turned it back on and it will freeze on the bios or do other crazy stuff.

If the console is left for 10 minutes it starts working again (For 10 minutes lol)

Is it the PSU?

 

You can measure the PSU output voltages to the console easily enough. As long as they're in spec it'll be something on the main board.

Look for suspicious bulging capacitors and replace them.

 

and also the diodes in the PSU. especially the schottky diode. they are worn out if its a voltek supply.

 

if you can remove the Caps and test with a DMM , i've learned from another forum they don't need to be bulging to be defective.

 

If you get buzzing in the power supply on subsequent bootups, then it is a known power supply issue, you have to change the TOP PWM IC and/or add an extra cap to reduce voltage ripples (I do both, just in case).

If the unit just randomly crashes or locks up after being turned on for a while, this is also a known issue, but we don't know the exact cause or fix. The only solution I found as of yet is to play with the machine regularly, as silly as it sounds, the lock-ups start happening when the machines are left unused for a long while. Recapping also helps but isn't an immediate fix.

It happens on all PSUs from VA0 to VA5 boards, including Voltek and including JP units. It just happens more often on some PAL units.

 

and also if you change the TOP chip. CHANGE THE DIODES! i have had several top chips explode after a change, when the diodes turned in to small value resistors. and I mean over 10 units. they short or go bad when the TOP goes.

 

I haven't had the diodes exploding, but if you do not clean up the bottom of the PCB when changing the TOP IC, then it is extremely easy for it to short out and explode.