Saturday, March 30, 2013

Bad RAM


Several situations can lead to RAM-related performance problems with a particular machine:
  • RAM timing is slower than optimal machine spec.
  • RAM has minor flaws that appear only on detailed testing.
  • RAM is overheating.
  • There is insufficient RAM.
In the old days of Fast Page RAM, buying new RAM for your computer was a simple affair. You just needed to know what speed your motherboard supported and the maximum each slot would take. Today, there are many types and speeds of RAM, and the better motherboards may be tolerant of using RAM that does not match the motherboard’s maximum specs. For example, your motherboard may support PC133 RAM but will still work with PC100 RAM. But be aware that you may see performance decreases if you install RAM that is slower than the maximum spec. Some motherboards will even allow you to mix speeds but will default to the slowest RAM installed.
Minor flaws in RAM chips can lead to system slowdowns and instability. The least expensive chips often have minor flaws that will cause your system to slow down or Blue Screen intermittently. Although built-in mechanisms may allow the system to keep working, there is a performance hit when it has to deal with flawed RAM chips.
In the past, no one worried about RAM chips getting hot, because they didn’t seem to generate much heat. But that’s changed with newer RAM types, especially SDRAM. To check for overheating, open your computer’s case, power down, and pull the plug out. Ground yourself and touch the plastic on one of your RAM chips. Ouch! They get pretty hot. If you find that your RAM chips are overheating, you should consider buying a separate fan to cool your memory. If your motherboard doesn’t support a RAM fan, you might be able to get enough additional cooling by installing a fan card that plugs in to a PCI slot.
Of course, one common reason for poor performance that’s related to RAM is simply not having enough of it. Modern operating systems such as Windows 7 and today’s resource-hungry applications, combined with our increasing tendency toward extreme multitasking, result in a need for more RAM. The minimal specified system requirements may not cut it if you’re doing lots of multimedia or running other memory-intensive applications. 32-bit Windows is limited to using 4 GB of RAM, but 64-bit Windows 7 can handle from 8 to 192 GB, depending on the edition. If your system allows, adding more RAM can often increase performance.

Mac Software Troubleshooting Tips


These days, many people try to claim that Windows 95, 98 and/or Windows XP and Windows 7 are "just as easy" as the Mac, but as soon as you scratch below the surface of each operating system, you’ll quickly discover that the Mac OS is still the better designed choice.
Nowhere is this more apparent than when it comes to troubleshooting common problems. Windows continues to show its ugly DOS-based history or some other arcane architectural flaw as soon as you start trying to fix something that goes wrong on your PC . The Macintosh, on the other hand, is generally much less prone to problems and those problems that do arise tend to have more straightforward answers.
But that doesn’t mean problems don’t happen on the Mac because they still do. In fact, for some people, they are maddeningly common. Sometimes the issues are hardware-related , but most of the time they have to do with software problems.
Staying Up to Date
One area where the Mac really isn’t that different from PCs is in the need to keep your software up-to-date. New application updates, operating system patches, and other types of upgrades are often the key to solving frustrating problems or just some annoying glitches. So, before you get too far into the troubleshooting process, take an inventory of your software and hardware and check to see if any updates are available online from the web sites of the companies whose products you use.
 don’t forget to check on any extensions you have installed, particularly ones that function as drivers for any hardware you’ve added to your Mac.
Extending the Mac’s Reach
Speaking of extensions, the vast majority of problems that pop up on Macintoshes are due to what are called extension conflicts. Before I get into what that means, let me tell you a little bit about how the Mac OS works.
When Apple designed the Mac’s operating system they knew they wouldn’t be able to provide all the features that people wanted, so they also built in a mechanism that lets Mac users add to or extend the capabilities of the OS very easily. This mechanism consisted of files called extensions that could, well, extend or alter the features of the operating system. By placing these files into a special Extensions folder inside the System Folder, they are automatically loaded and run whenever the Mac starts up.
The only time most Mac users even become aware of extensions is during the startup, when the little icons representing different extension files dance across the bottom of your Mac’s screen. (Not all extensions have startup icons, by the way, so don’t presume that because you counted 8 or 10 different icons during the startup, or boot, process that’s all you have. Most Macs have at least 40 or 50 extensions and many have 100 or more.)
The way that many—though not all—Mac extensions work is that they are loaded into memory along with Mac OS at startup time and stay there until you shut down. So, for example, if you have an extension file like Adobe’s Type Manager, it adds its type-rendering features to the operating system as your Mac starts up, and stays there as an "extension" to the operating system for as long as your Mac is on.
The benefit of this arrangement is that any and all programs that run on your Mac and need access to the features offered by the extension can get to them by interacting with the operating system, as they normally do. The downside, however, is that some programs don’t operate correctly when used in conjunction with certain extensions or certain versions of specific extensions. In addition, some extensions step on each other’s toes by providing some of the same types of changes to the Mac OS. Others simply make changes in a way that conflicts with each other.
Finally, the last drawback of this arrangement is that if you’re using applications that can’t or don’t take advantage of the features offered by certain extensions, you’re wasting precious Mac memory. The reason is, once an extension has been loaded into memory it stays there and continues taking up space until you shut down your Mac. As we move towards larger and larger amounts of RAM this concern is becoming increasingly less important, but it’s still there.
By the way, if you ever want to see just how much memory your extensions use, try this simple procedure. First, do a normal Mac startup and when you reach the desktop, go up to the Apple menu and select About This Computer (or About This Macintosh or whatever the message on your machine happens to be) to see a display of how much memory each application on your Mac is currently using. Make note of how much the Mac OS, or System, is using. Now, restart your Mac holding down the Shift key until you see a message about No Extensions (I’ll explain what this means in a bit) and when you get to the desktop, go to the Apple menu again and select the same menu item. You should see a dramatically lower amount of memory being used by the Mac OS, or System, in this case. The difference between the two is the amount of memory that your extensions are using.
Extensions Manager to the Rescue
So, what’s the trick to solving Mac extension conflicts? Using the Extensions Manager that’s been built into the Mac OS since System 7.5,. Either program lets you selectively turn off individual extensions or groups of extensions at startup time so that you can try and figure out what’s causing the problem. They also let you change the order in which the extensions are loaded, which can also make a difference. Some extensions need to be loaded last or near the end in order not to conflict with others.
To get to Extensions Manager (which is actually a Control Panel), you can hold down the space bar while you’re starting your Mac, or choose Extensions Manager off the Control Panel submenu under the Apple menu while your Mac is already running. Conflict Catcher lets you assign a hot key to launch it during startup but it also defaults to the space key. Essentially what you do with either utility is select a group of extensions that you want to keep "on" and a group that you want to turn "off" and then after your computer starts with the set of extensions you’ve chosen, you try to recreate the problem you were having.
In some situations, extension conflicts can keep your Mac from booting at all. If you only make it part of the way through the startup process and then your computer freezes up, then that’s the classic sign of an extension conflict. (A partial boot can also be a symptom of a hardware-based SCSI problem, If it does turn out to be an extension-related problem, you’ll know you’ve found the problem when the Mac makes it through the startup phase and brings you to the desktop.
Some extension conflicts don’t occur during startup, however. If you’re having trouble running certain applications or groups of programs, you’ll want to check those after you’ve selected a different set of startup extensions. If the same problem occurs (or if your Mac still can’t boot), then you haven’t found the culprit and you’ll need to select a new set and go through the process all over again.
As you might expect, finding extension conflicts can be very slow and tedious (aren’t computers grand!), but Conflict Catcher makes it a bit easier by automating the testing and restarting process to a certain degree.
By the way, in addition to turning off certain extensions to avoid conflicts, you can get more memory for your applications by turning off extensions that you aren't regularly using. As the above example shows, extensions can take up a lot of memory and turning off a bunch of them (or even sometimes just a few of them) may give you several megabytes of RAM space back.
Giving Yourself Enough Room to Work
Speaking of RAM, another problem that can occur with Macs is running out of memory. Like PCs, Macs take advantage of something known as virtual memory, which basically uses some space on your Mac's hard drive to "fake" the system into thinking it has more real physical RAM than it actually does. So, for example, a system with 32 MB that uses virtual memory might appear to the MacOS as having 64 MB of working room. You can turn virtual memory on and off via the Memory control panel. In most instances you'll want it on, but there are some older applications that won't work properly with it turned on, so you should check your Mac's settings and adjust them as necessary.
A practical benefit of virtual memory is that it gives your Mac enough room to open up multiple applications. However, it doesn't necessarily impact how much memory each application has to use, nor does it automatically increase the amount of memory allocated to each application as needed. Instead, the amount of memory allocated to each application is determined by an obscure setting in the application program's Get Info box. To find this, click on the application you want to check in a Finder window and select Command (the clover key)-I or select Get Info from the Edit menu. (You have to do this on the original application file, not an alias.)
Inside the ensuing dialog box you'll see a reference to the minimum amount of memory required by the application to run, as well as a preferred amount. If you increase both those numbers (they're often in Kilobytes, so divide by 1,024 to figure out the amount in Megabytes), you'll increase the amount of memory the application has to do its own work. This can be very handy if you're working with large or complex documents because if the application doesn't have enough room to do its work, you may get an error message saying there isn't enough memory even if you have lots of RAM installed and it's the only program running.
You don't want to increase the amount too much, however, because these numbers affect how much memory the MacOS sets aside for the application. If the application has way more than it needs, you'll just be wasting memory. So, the trick is to find an amount that lets you work without getting out-of-memory messages, but doesn't take more than necessary. By the way, if you have only one or two problematic documents, you can always just adjust the application's memory allocations--which is what these numbers are called--right before you work with them, and then change them as soon as you're done. You can't change them while the application is open, but otherwise it can be done at any time.
Problems with Preferences
Another fairly common problem on Macintoshes has to do with preference files, which are files used by most applications to store certain settings they need to operate properly. If you’re having problems with a specific application, it may be due to a bad or corrupted preferences file.
There’s no easy way to tell by simply looking at a preferences file whether it has a problem, but there is a simple procedure you can try if you suspect a problem. Just open the Preferences folder inside your Mac’s System Folder, look for the preferences or "prefs" file for the particular application, and drag it into the Trash. Most applications will automatically create a new preferences files the next time you start them if they can’t find an existing one in the Preferences folder.
In some cases you may have to reset any adjustments you had previously made to the program’s preferences or settings dialog box, but that’s a small price to pay to get your application working again.
Viruses and Other Issues
Mac users were very fortunate for many years because the Mac OS was fairly free of computer viruses. Recently, however, that situation has changed and now Mac users also need to be on the lookout for viruses (such as AutoStart Worms), Trojan Horse programs (which hide bad things in a seemingly innocent package—hence their name), and other nasty stuff that can wreak all kinds of havoc on your Mac.
If you’re encountering strange problems, such as a Desktop Print Spooler that keeps launching and won’t go away, you may have contracted a virus. To fix that problem and/or avoid getting any viruses in the future, make sure you purchase and install an anti-virus program such as Norton AntiVirus  and, most importantly, keep the virus definitions up to date. New computer viruses are being developed and unleashed at an alarming rate and even if you have the most recent version of an anti-virus program, you may still be at risk if the virus definitions—which is what looks for and erases specific viruses—aren’t current.
The End
There’s no question that the Macintosh and the Mac OS are great products, even if they aren’t quite perfect—yet. If you do run across problems, bear in mind some of the previous tips, use some of the available resources and you should be able to keep your Mac in top working form.