21.5" Mid 2010 Imac RAM issue and replacement SSD

[mcnallykev]

Hi All,

I have had my mac from new and enjoyed it thoroughly. Recently (I was running 16GB RAM) the mac wouldn't turn on. After various tests I wont bore you with I got it running with 2GB. It will not run with any more than that.

If I put more in regardless of configuration it gets stuck in a start sequence where I can hear it turn on but there is no display and after about 15 sec it restarts itself and carries on going in that circle.

I have reset the NVRAM to no avail so have resigned myself to running on 2GB as I don't want to splash out on a replacement.

Which leads to the SSD. As a way of increasing performance I have bought a samsung 500GB 850 EVO SSD. Subsequently I have become aware of the KEXT problem. The drive isnt installed yet as is on it's way to me.

Should I install this before I start doing anything and with the old drive in situ. http://www.hackintoshosx.com/files/file/4279-kext-utility-yosemite-258/

(Apoloies if I'm not allowed to post this)

Grateful for any advice.

Kev

 

[chscag]

Ignoring your more difficult problem (memory) for now..... the Samsung SSD will work but since you're running Yosemite, you will be unable to get TRIM support for it. Otherwise the drive should work, albeit slower than if you had TRIM support.

However, you really need to re-think your overall strategy with the iMac. Memory modules do not all of a sudden fail, especially to where you can only run 2 GB in a machine that can take 16 GB. I would guess you have a logic board problem, possibly the GPU, or something else. You really need to take the machine to an Apple store and let them run diagnostics on it. The diagnostics are free as long as you use an Apple store.

You can overcome the TRIM problem by downloading "Trim Enabler" but be sure to read all the developer's caveats about using it.

 

[mcnallykev]

Thanks for the info. I was worried it would even boot. I will get in to an apple store and have it checked over. I believe Logic boards are v expensive.

Thanks again.

 

[Lifeisabeach]

There's also the possibility the RAM you are using is faulty (though chscag is right... they don't normally fail out of the blue). How long have you had those modules and where did you get them from? You should always use exact matched sets of modules or problems may arise.

As fot the issue with Yosemite and TRIM, I'd recommend switching to an SSD that doesn't really need it. OWC sells SSDs using the SandForce controller, and their stance has long been that TRIM is not only unnecessary for their drives, but can actually shorten their lives. I would take their word on this... these guys are experts on Mac upgrades. I would return that Samsung and get one of OWC's drives instead. I've been using one myself on the same model iMac as you for a couple years now I guess, and man oh man did that breathe some life into this!
With An OWC SSD, There’s No Need For TRIM | Other World Computing Blog