Mac mini works only for few minutes

[MassimoD]

HI all, a couple of weeks ago a friend of mine gave me an old macmini1.1 that, according to him, was not working at all. When I tried to start it I had mixed results: sometimes it started, sometimes it freezes on a white screen but all the times it didn't last for more than two or three minutes.
I've obviously reset smc and nvram, I changed the HDD (with a SDD) upgraded the CPU to a t7200 and changed the firmware to 2.1. The bank1 started to fail (I'm sure when I started, the mini recognize both 1gb sticks, now if I put a stick of ram in bank1 the Mac won't start, it only blinks the white led, with ram in bank0 only, it starts). I even changed the Ram (1 stick of 2gb 5300s). And I've been even able to install a brand new copy of Lion. But I always have the same issue: sometimes it doesn't start (I have to try two or three times) and when it starts it doesn't last more than few minutes before hangs (videos, mouse and keyboard are totaly unresponsive) and it must be shutted now via power button. The temperatures are little high (CPU 50/60° With no program running, only istatmenu) but not too much (it's hot here in Italy).
Don't know how to troubleshooting. I think it must be something related to logic board. Any suggestion

 

[twalk]

With a computer that old (~12 years), about anything can go wrong with it. For example, on a board that old, you can get tiny cracks in the soldering or "whiskers" in which the solder spreads over time and connects lines that are supposed to be separate

I'm not saying that it can't be something easier to fix, but with a computer that old, you have to take in consideration that there's a number of things that can fail that you'd otherwise ignore in a newer computer and/or are really difficult to find

 

[MBAir2010]

Seems like the Video card is defected on the motherboard, that happened to my iMac g4 years ago.
The motherboard needs to be replaced.

 

[Cape Dave]

It is old and tired and needs a long nap with the fishes.

 

[Partron22]

Tried re-updating the firmware?

 

[MassimoD]

I know, it's a rather old piece of hardware, but I feel so sad to trash away such a beloved machine. It was my first Mac and I still use, as a back up notebook for light works, a similar MacBook Pro core duo 2, so I guess that it should be still useful somehow. Unfortunately the logic board for this model are very hard to be found here in Italy, and they cost definitely too much (more than 100$).
I still haven't tried to re update the firmware. That could be a very last try before surrend to reality.

 

[Partron22]

Try 1gB memory total. That was the original spec for the thing. Your 2X2 with updated firmware should get you to 3gB usable.
Mine still works fine under 10.5 with 1gB memory. I'm probably getting near the end of the bell curve though, 13 years.
When it goes, I'll likely replace it with a Raspberry Pi + Kodi. -Be nice to see them move to USB 3 first though.

 

[MassimoD]

Already tried, even with only 1gb still hangs after few minutes. I am quite sure isn't a problem of temperature also. Last time I've tried it froze after a couple of minutes and istatmenu reported 45° C for the CPU.
At this point it's clear that is an hardware issue. The only reasonable fix would be a new logic board.

 

[Partron22]

EU compliant solder? That stuff at least used to have the habit of growing metal whiskers. You might check the board with a magnifying glass. Could be a whisker causing an improper connection. Beyond that its new logic board or trash time.

 

[Snappers]

Already tried, even with only 1gb still hangs after few minutes. I am quite sure isn't a problem of temperature also. Last time I've tried it froze after a couple of minutes and istatmenu reported 45° C for the CPU.
At this point it's clear that is an hardware issue. The only reasonable fix would be a new logic board.

I have a mini 1,1 that I retired last year. I need to get rid of it. Do you want it? Send me a PM and we can work something out.