Reply To: Dreamcast sync issues w/ firmware 0.77a

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Just got my OSSC 1.6 and can confirm this issue is still present. Same symptoms described by the OP. Everything is perfect, then intermittent black screens and eventually no signal. I was playing Phantasy Star Online on the Dreamcast at the time for about 15 minutes before the issue presented itself. I am using the recommended DTV setting and a Kuro VGA box with a brand new VGA cable. I’ll try to reproduce the issue and see if I notice anything else. Does anyone know if there is anything I should try or anything helpful to look for?

I just tested the same scenario (PSO on DC via VGA) and I am quite sure that the problem is in fact thermal.
Here is the timeline of my testing:

– 15 minutes in game –
First loss of HDMI signal

– 21 minutes –
Second loss of signal event

– 22 minutes –
Third event, signal becomes intermittent at this point, occasionally recovering for up to a minute

– 26 minutes –
TV reports unsupported signal (audio stutters through for a second or two every minute or so but no picture)

– 30 minutes –
No change in 4 minutes, I restart the OSSC by toggling the on/off switch, the test pattern appears, I set AV3 input, everything works, a few seconds later the signal drops again, and returns intermittently

– 32 minutes –
Once again total loss of signal, I turn off the OSSC and leave it off for 30 seconds, once set back to AV3 the signal is back and stable

– 35 minutes –
Signal drops again

– 36 minutes –
Constant signal drops, I turn the OSSC off and leave it off for one minute

– 37 minutes –
Back on, signal stable

– 40 minutes –
First signal drop

– 43 minutes –
Total loss of signal, I blow onto the small copper heat-sink visible through the hole for the power switch for 15 seconds, the picture returns and is stable for several minutes

I repeated the last procedure a few times for sanity’s sake: Wait for the signal to stop completely (not intermittently dropping) and then restore the signal simply by blowing on the heat-sink. For reference, the room was around 20 degrees Celsius.

It seems that either my heat-sink was seated improperly at the factory or that the heat-sink itself is of insufficient size (albeit barely – the tiny amount of heat build up removed by blowing on the heat-sink shows that it is very close to being able to dissipate the necessary thermals).

Not sure what to do about this, but hopefully this helps someone, I really don’t want to return this thing to the UK (I’m in the USA), but I also don’t really feel like installing a new heat-sink – although that seems like the best course of action at this point – assuming I can find a bigger one that will fit.