Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a MSI 945pl/neo 5 motherboard with 1 GB DDR2-667 DIMM. Two days ago I bought an additional 1 GB DDR2 DIMM from my friend. Its used but it was working on my friends computer.

If I install the new DIMM in the second green memory slot (which is a different channel) then the computer stays stuck in the POST screen.

If I install the new DIMM in a orange slot (thus configuring it for use as dual channel memory) then the fan starts, but the screen stays black. (Not even POST).

When I remove the new DIMM the computer works fine.

Please help.

share|improve this question
The bios usually beeps there and gives you a beep code at this point, is that the case here? Which code is it? Do you know how much and which type of ram your motherboard supports? – superuser0 Apr 13 '13 at 7:31
yah it beebs just once and give me the bios screen and stuck there. i remember that i wrote it in the question but i dont now itsnt there maybe i forgot to write it...thanks for your answer i hope you help me – amjad22222 Apr 13 '13 at 7:35
it supports only 2gb ddr2 of ram 400/533/667 – amjad22222 Apr 13 '13 at 7:37
Is your friend's ram the same speed as what's all ready in the machine? Some systems require pairs of identical memory to be inside in certain slots and they have to filled in a certain order. Do you have any documentation on the motherboard? – martineau Apr 13 '13 at 7:41
could it be a problem in the timing of the rams because computer boots to the bios screen and stuck and the bios screen goes slowly on the screen. – amjad22222 Apr 13 '13 at 7:46

According to the manual for your motherboard you have four memory slots. Two are coloured green, two are coloured orange.

Picture of the relevant motherboard

The manual also specifies the following things:

  • Your board supports either DDR1 or DDR2. However you can not mix these two. You need to use either all DDR2 or all DDR1. You wrote that the new DIMM is DDR2 667. Check if your old DIMM is also DDR2
  • Your motherboard support dual channel memory access if you put one DIMM in a green bank and one identical DIMM in the matching orange bank. You can not always do this if the DIMMs have different timings. (Sometimes the MB/BIOS will select the slowest combination of both timings, sometimes it just will not work).


First remove both DIMMs. Put them net to each other and compare the notches to check if both are DDR2. This picture from Wikipedia might help.

DDR1/2 DIMM picture from WIkipedia

If they do not match you simply can not use both.

If they both are DDR2 then try to boot the motherboard with one DIMM. Try both of them. This will verify that your computer is compatible with the new DIMM. (They usually are, but sometimes boards and DIMMs do not work well in combination, without any clear reason).

Third step:
Check the timings for the DIMMs. Are they equal speed (same CAS, RAS, ...)? DoO they require equal voltage? If they match it should work if you put one DIMM in the first green slot, and one in the matching orange slot. If it does not try moving both to the green slots, which will use both DIMMS as single channel, rather then trying to combine the two into dual channel access

If this does not work either then please add more details to your original post.

Specifically expand and clarify the part where "I tried different combinations and the only one that gives me something different".
(Something different? Just what is different?)

share|improve this answer
first of all thanks for answering . – amjad22222 Apr 13 '13 at 9:48
first of all thanks for answering .the diferent that when put my new ram in the vacant remaining green slot(both rams now in green slot) the computer stuck in the POST screen but other combination makes the computer run and the fan runnung but the screen stays black the whole time....the old ram is ddr2 667 but the new is mysterious nothing specific to read like the previous picture does – amjad22222 Apr 13 '13 at 9:57
I added this to your post so it is easy to find for everyone without reading all the comments. If you do not like the way I edited your post you can revert it, or you can use the EDIT link below the post. – Hennes Apr 13 '13 at 10:08
no i like it but i want to know what to do – amjad22222 Apr 13 '13 at 10:21
actually i like it a lot thanks – amjad22222 Apr 13 '13 at 10:22

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.