memory problem

Benbow · 31 Oct 2010

I am running windows 7 and I have four DDR2 memory slots each with a capacity of 2gb. Since installing Win 7 I have increased the memory from 2 x 1gb to 2 x 2gb with 2 spare slots.
I am trying to install a further 2 x 2gb of identical memory in each of the 2 spare slots but when I boot up about 30 seconds later the machine crashes - no blue screen, a simple lock up.
When I remove the 2 extra memory leaving the existing 2 x 2gb in place the machine boots up and runs normally. Any ideas why adding the extra memory causes a crash?

TVeblen · 31 Oct 2010

There are a few possible causes for this behavior:

Bad/defective RAM sticks
Bad/Defective RAM sockets/motherboard
Insufficient power being supplied to the RAM slots
Mis-matched RAM specs/timings (you seem to have that covered)

You can test the individual RAM sticks using Memtest86+ and installing one stick at a time in Slot #1 to run the test. (be sure to mark/number the sticks if they are identical)

You can test the slots by populating the #3 and running Memtest, then #4.

You can test power issues by going into the BIOS and increasing the voltage for the RAM in small increments and testing. Do not exceed any motherboard limit mentioned in your manual.

Hope that helps.

Benbow · 31 Oct 2010

I have tested the memory and the slots and all are ok. It will work with 3 x 2gb installed but when I put in the fourth.......crash. Is it something to do with a bios setting?

Solarstarshines · 31 Oct 2010

try switching the sticks around in oppesite slots then boot into bios and check what settings the memory is on make sure it is in accordance for the clock speed of the ram

you might have a voltage issue in one of the memory ports

zzz2496 · 31 Oct 2010

Check BIOS update, most of the time - these kind of problems are solved by BIOS updates...

zzz2496

EzioAuditore · 31 Oct 2010

BIOS update and setting the voltage controls to auto. Let the BIOS determine the correct power..

Solarstarshines · 31 Oct 2010

zzz2496 said:

Check BIOS update, most of the time - these kind of problems are solved by BIOS updates...

zzz2496

also to add some bios updates underclocks speeds as well

bobkn · 31 Oct 2010

Benbow said:

I am running windows 7 and I have four DDR2 memory slots each with a capacity of 2gb. Since installing Win 7 I have increased the memory from 2 x 1gb to 2 x 2gb with 2 spare slots.
I am trying to install a further 2 x 2gb of identical memory in each of the 2 spare slots but when I boot up about 30 seconds later the machine crashes - no blue screen, a simple lock up.
When I remove the 2 extra memory leaving the existing 2 x 2gb in place the machine boots up and runs normally. Any ideas why adding the extra memory causes a crash?

You don't list your motherboard type.

Asus, for example, produces a QVL (qualified vendors list) for some of their boards. Some RAM is able to be used in all the slots. Some only is certified for two slots.

You may be able to get your RAM to run by manually setting its voltage and timings in the BIOS setup. It's similar to overclocking the RAM, except you're just trying to get 4 sticks to run reliably.