iMac A1311 late 2009 relectant starter

[johnn635]

This machine had a faulty HD4670 MXM graphics card, cured by reflowing and has run for 18 months. Now it will start and run normally provided the NVRAM reset keys are held until it does - sometimes a couple, sometimes 20 or more chimes needed. It then operates entirely correctly. Normal video and all devices.

If allowed to sleep, it may need the same treatment. NVRAM battery is 2.9V. Date and time are stored. High Sierra even files a 'fail to wake from sleep' report.

Based on the above, and assuming a bad cap somewhere, any previous experience? The SMC is the obvious area.

A working iMac is still useful, but intermittent is frustrating.https://www.badcaps.net/forum/images/icons/icon8.gif

[piernov]

Re: iMac A1311 late 2009 relectant starter

What are the symptoms when it doesn't work?
The graphics card is good for the garbage bin anyway.

[johnn635]

Re: iMac A1311 late 2009 relectant starter

LED#1 and LED#2 on. LED#3 not on, so no video. Resetting NVRAM/SMC makes LED#3 ( and LED#4 if screen attached.) Easier to work on with screen removed and external monitor on DP.
Throwing away the graphics card = throwing away the iMac.
John

[piernov]

Re: iMac A1311 late 2009 relectant starter

Does it chime at least?
Well the graphics card is dead in any case.

[johnn635]

Re: iMac A1311 late 2009 relectant starter

Language problem? OP said 20 or more chimes. Also how can card be dead if it is working normally when it finally starts.
Forum is Badcaps and these are the symptoms of a bad cap. Was asking if anyone had experience in this area. Apparently not.

[SMDFlea]

Re: iMac A1311 late 2009 relectant starter

Language problem? OP said 20 or more chimes. Also how can card be dead if it is working normally when it finally starts.
Forum is Badcaps and these are the symptoms of a bad cap. Was asking if anyone had experience in this area. Apparently not.

You are assuming its a bad cap. @piernov does have experience in this area, he`s forgotten more than you will ever know. If you want help just answer the questions asked.

[johnn635]

Re: iMac A1311 late 2009 relectant starter

Hi SMDFlea,
auto logout removed my constructive response, so I will forget this request.

[piernov]

Re: iMac A1311 late 2009 relectant starter

You already confirmed GPU is dead by "reflowing". Of course something else could be wrong, but dead GPU is a good reason for it not to initialize properly…

[johnn635]

Re: iMac A1311 late 2009 relectant starter

Like I said - language problem. Dead bodies don't breathe. Sick, maybe. Sorry to waste your time