ram problems

Hi there to ALL and @tsialex , I would like to ask you for some specific unrecovered MacPro 4.1/upged to 5.1 PROBLEM I have 2 CPUs board and Iam not able to use any of 5–8 RAM slots - With tem MAC not boot or unattended shutdowns ... I realy does "everything" from 12 different 100% checked sets...

Recently I'm getting three repeating sets of beeps with my original set of Kingston 2 x 4gb sticks of ram. So I've tested each stick separately in each bay and they work fine. No beeps when only one stick is in either bay. I've reset the PRAM, etc. Then I purchased two sticks of 8gb from...

My MacBook Pro 15" 2.5 GHz (late 2011), purchased in October 2012 at an Apple authorised reseller, has started to do random reboots and demonstrate odd video behaviour which is the classic symptoms of the known graphics card failure of these particular macs...broken up video and offset screen...

I have a 2010 macbook pro 15 inch icore 7. I bought it used and it was running with only one stick of 2g ram. I bought 2 sticks of 4g ram for it but it wont start when they are installed. I currently have 3 macbooks and interchanged all the ram sticks between the different macs to make sure...

Currently we have a Mac Mini (late 2012) Running El Capitan 10.11.6 (most current as of time of post), here are the specs: 2.3GHz intel 4 core i7 16GB 1600 MHz DDR3 1TB 5000 RPM boot drive (no files stored) Promis pegasus 2 r8 Raid 12TB usable (x2 one for time machine back up) Both pegasus are...

An experience that may be useful to others: Have had strange problems with my mid 2011 imac: freezing, functions in various apps like Indesign stopping working, half the keyboard ceasing to work, intermittent bluetooth mouse, browser issues and a few other oddities.... nothing I found on the net...