What's are the effects of using lower quality RAM?
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From: Bernard Peek on 18 Jul 2010 06:38 On 18/07/10 00:36, Nigel Lord wrote: > > Thanks for this - all three people who took the time to reply. > > I know that the received wisdom is 'stick to good quality RAM', but my > question was simply, what is the likely outcome of using less good > quality RAM - assuming that it is actually compatible and that it does, > broadly, work (which in this case it must, otherwise I wouldn't be > writing this!). > > In other words... can RAM work, but work less well - and how does this > reveal itself? > It could work perfectly, it could crash repeatedly or anything in between. Lower quality memory will make the system less reliable. So the symptom would be more frequent crashes. -- Bernard Peek bap(a)shrdlu.com
From: Rowland McDonnell on 18 Jul 2010 13:13 Jaimie Vandenbergh <jaimie(a)sometimes.sessile.org> wrote: [snip] > To test the RAM, you can use the > Apple Hardware Test extended mode (boot off the install DVD while > holding D to get into AHT), or better by getting+burning a memtest86 > iso and booting off that. If you'd read my post,s you'd know that there's a much easier way. http://applejack.sourceforge.net/ - comes with memtest, and instructions. Rowland. -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking
From: Mark Ingle on 18 Jul 2010 17:49 Nigel Lord <nige(a)room.bt.com> wrote: > > So my question is... can the quality of RAM affect a Mac in this way? I > suspect the kernel panic is RAM-based, but what about applications > quitting for no apparent reason? Is there any way that you can test the > integrity of your RAM? And what troubleshooting app would anyone > recommend to identify potential software problems? I do tend to get my RAM from Crucial though even then I have had the odd problem and Crucial have sent me out a replacement. Because it can be time consuming to diagnose crashing and other issues I think it pays to get decent memory; at work we used to get the cheap generic memory from Misco but not anymore - I only get Crucial or Kingston. For the Windows computers at work I use the memory checker that comes with the Ubuntu CD installer which has confirmed when I thought the issue was RAM related, though I've not tried using it on either of my Macs as thankfully I've not had any RAM issues - on my older MacBook I have Crucial memory and on the newer one it is Apple's. If you have two SODIMMs you can always whip one out and see whether it resolves your issue.
From: Bob Whoredrope on 19 Jul 2010 02:28 On Sun, 18 Jul 2010 01:08:40 +0100, Rowland McDonnell wrote: > Nigel Lord <nige(a)room.bt.com> wrote: > >> I've just bought a new Mac Mini as a replacement for my G5 PowerPC - >> primarily to allow me to upgrade to Adobe CS5. I thought it wise to >> max out the (SODIMM) RAM to 8GB and having picked myself up off the >> floor after discovering Apple's price for memory, spent a couple of >> hours trawling the internet for something more affordable. One of the >> sellers I found - KOMPBAY - was advertising 2 x 4GB at around �160 - at >> least �50 cheaper than anyone else - so I placed my order. > > There's always a reason for things being cheaper, if you see what I > mean. Make sure you know what the reason is - it's usually not because > it's a bargain for the buyer, I can tell you. > >> Prior to installing the RAM, I was plagued with crashes and other >> problems which I put down to running Photoshop and other apps with only >> 2GB of memory. > > You should not have any crashes if RAM is low. If you do have crashes > that don't turn up until you're filling all your RAM, that /might/ > indicate that your RAM is dodgy, just not much of it's dodgy. > > How to find out? > > Get Applejack and follow the instructions on using memtest which is > included with Applejack: > > <http://applejack.sourceforge.net/> > >>However, now with 8GB memory, I'm still suffering >> unexplained crashes - even the odd kernel panic - which I am at a loss >> to explain, given that the machine is so new. > > It's defective RAM - not up to spec. This is exactly what you'd expect > from dodgy RAM. It's cheap because it's dodgy - not up to spec. > >> I've even had this weird incident where the screen turns blue - the Mac >> doesn't audibly re-start - but when it comes back on screen, all the >> apps have quit and it looks like it has re-started. > > Fun and games :-) > >> So my question is... can the quality of RAM affect a Mac in this way? > > If the RAM's not up to spec, you can expect this sort of thing. If the > RAM is up to spec, you won't. > > Basically, you've fitted your Mac with broken parts and it's not working > right as a result. > >> I >> suspect the kernel panic is RAM-based, but what about applications >> quitting for no apparent reason? > > Sounds about right. > >>Is there any way that you can test the >> integrity of your RAM? > > Use memtest - comes with AppleJack. > > <http://applejack.sourceforge.net/> > > And do follow the instructions... > >>And what troubleshooting app would anyone >> recommend to identify potential software problems? > > I'd start out by looking in the various logs you can get to see using > Console.app in /Applications/Utilities. > >> OK... I know that's three questions, rather than one - but if anyone >> could shed any light, I'd be most grateful.... > > You've got duff RAM - send it back, buy some decent RAM. > > Rowland. Not so good Rowlie. Four posts and no replies. I think they've sussed you out. -- "Oh and there is very little that Rowland actually likes. He hates the world, basically." Sarah Balfour dumps on Rowland McDonnell - Oct. 26, 2007
From: Gordon on 19 Jul 2010 04:40
On Jul 17, 7:17 pm, Nigel Lord <n...(a)room.bt.com> wrote: > I've just bought a new Mac Mini as a replacement for my G5 PowerPC - > primarily to allow me to upgrade to Adobe CS5. I thought it wise to > max out the (SODIMM) RAM to 8GB and having picked myself up off the > floor after discovering Apple's price for memory, spent a couple of > hours trawling the internet for something more affordable. One of the > sellers I found - KOMPBAY - was advertising 2 x 4GB at around £160 - at > least £50 cheaper than anyone else - so I placed my order. > > Prior to installing the RAM, I was plagued with crashes and other > problems which I put down to running Photoshop and other apps with only > 2GB of memory. However, now with 8GB memory, I'm still suffering > unexplained crashes - even the odd kernel panic - which I am at a loss > to explain, given that the machine is so new. > > I've even had this weird incident where the screen turns blue - the Mac > doesn't audibly re-start - but when it comes back on screen, all the > apps have quit and it looks like it has re-started. > > So my question is... can the quality of RAM affect a Mac in this way? I > suspect the kernel panic is RAM-based, but what about applications > quitting for no apparent reason? Is there any way that you can test the > integrity of your RAM? And what troubleshooting app would anyone > recommend to identify potential software problems? > > OK... I know that's three questions, rather than one - but if anyone > could shed any light, I'd be most grateful.... > > Nige If your RAM is faulty, you will see all kinds of weird issues, including a lot of crashing. You can use Memtest to verify that your RAM isn't faulty. It won't catch every possible failure mode (as some need specilized test hardware that's not available to consumers) but it does have a very thorough battery of tests and will certainly catch faults that the standard power on tests won't. http://www.memtestosx.org/ |