- How many errors are acceptable?
No errors are acceptable. Even if there is just one error, something is
amiss which can cause your system to crash. Of course what the cause of the
errors is you will still have to determine.
- What do I do when I get errors?
Firstly, don't start drawing any conclusions. You only know that memtest86+
is giving your errors, not what the cause is. Unfortunately it is not a
straightforward exercise to decisively test the memory in an actual system.
This is because a computer is not just built up of some memory, but also
includes many other elements such as a memory controller, cache, a cache
controller, algorithmic and logic units, etc, all of which contribute to the
machine. If there are faults in any of these other parts of the computer you
will likely also see errors showing up in memtest.
So what to do? First verify that the BIOS settings of your machine are
correctly configured. Look up the memory timing settings applicable to the
brand and type of memory modules you have and check they match your BIOS
settings, correct them if they don't and run memtest again
Ok, you have all the settings correctly set and you're still getting errors.
Well of course a very likely cause are the memory modules and the logical
course of action is to look into them further.
If you are well stocked, have a few other machines at your disposal, or just
want to spend the cash for some new modules the best way to test if the
cause are your memory modules is just to replace them and test again. If you
are less fortunate though there is still something you can do.
If you have more then one module in your system, test them one by one, if
one is consistently giving errors and another is consistently showing no
errors it's a pretty good bet that the module giving the errors is simply
defective. To exclude the possibility that a defective slot is throwing your
results, use the same slot to test each different module.
If each module by itself shows no errors, but when you place two or more
modules into the machine at the same time you do get errors, you are most
likely stuck with a compatibility issue and unfortunately there isn't a
whole lot you can do about it. Be sure to check your computer/motherboard
manual to see if the setup you are trying is allowed, some boards require
special restrictions in the sizes of modules, the order of modules, the
placement of double sided and single sides modules and more of such things.
If you have only one module in your system, or all modules are giving
errors, there are only very few options left. The only thing you can do
really is to try the module(s) in another slot. Finally simply try out
different orders of the memory modules, although your manual might not
mention anything on the matter sometimes there simply exist timing or other
issues which can be resolved by changing the order of your modules. And of
course test each slot by putting a single module into that slot and running
memtest on it.
In the end if you still have not been able to localize the problem you will
have to find a replacement module to establish whether the problem lies in
your modules. See if you can borrow a module from someone else.
When you have replaced the memory by new memory and the errors still
persist, first check if you can rule out any compatibility issues or timing
issues. If you are sure the memory should work in the system the cause of
the errors must obviously lie someplace else in the system.
The only way to find out where, is by trial and error really. Simply start
replacing and/or removing parts of your computer one by one, running memtest
each time you changed anything, until the errors are resolved.
