Windows 7 64 bit wont boot after installing RAM

[RELEASE_THE_KRAKEN]

Hello,

I recently decided to add 4 more GB of ram to my system, but when the sticks are inserted windows wont boot. Currently I have 2 GB of this ram: Newegg.com - BUFFALO Firestix 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model FSX800D2C-K2G .My system has ran fine with the Buffalo Firestix.

When I add two more sticks of corsair 2MB to the system (two of these: Newegg.com - CORSAIR 2GB 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Desktop Memory Model VS2GB800D2 G) for a grand total of 6 GB, windows wont start. The four sticks are of the same speed (2 are buffalo and 2 are corsair).

More Information:
I've looked in the BIOS when all the sticks are inserted and the bios displays 6 GB of memory which is correct, yet no windows boot. I have tried inserting the new sticks into the slots of the old sticks, no go. I also tried using one new stick along side with an old working stick, no go.

I have windows 7 64 bit
Here is the motherboard I have: Newegg.com - MSI P6N SLI Platinum LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard

Any idea on what the problem could be?

UPDATE: I just tried running my system with a single stick of the corsair (2 GB) and it works. Is there possibly an option in windows 7 somewhere that you have to set the amount of ram allowed?

[Darkpowder]

It could be a number of problems, voltage, incompatibility etc.

Check your motherboard manual in detail as to what type of memory is compatible. Sometimes even running more of the same memory you are using will not function with default motherboard settings.

Check google/forums for others using the precise designation of RAM you are using with the precise model number of the motherboard.

Sometimes (though be careful) reliable instructions advise you change memory timings or voltages to make them function, but remember that some of these instructions are for overclockers - though sometimes the same techniques are used to make them work.

Multiple memory vendors can cause problems on some motherboards. My advice is to research very carefully which mobos are very forgiving for memory types, rather than just the "features included".

Sometimes identical memory from the same vendor will cause a problem, go back to your original memory configuration before the 2gb expansion, do some research and send the new memory back for a refund until you have it researched what memory you will need.

[SocketMan]

Take out the 2 old sticks, and just use the new 4gb kit.
Most motherboard won't work with different density sticks (when set to auto in the BIOS).

[RELEASE_THE_KRAKEN]

Take out the 2 old sticks, and just use the new 4gb kit.
Most motherboard won't work with different density sticks (when set to auto in the BIOS).

I have tried that but windows still wont boot.

I know for sure that both corsair sticks are good because I have tested them individually and windows boots right up (I have also tested every DIMM slot with a successful boot-up). Its when I use the two corsair sticks together windows won't boot.

thanks for the advice Darkpowder, Ill see what ram works for sure with my mobo.

[SocketMan]

Try setting the timings manually in the BIOS,if you haven't already.Use 2T,instead of 1T.

If the ram is good then the AUTO timings are probably to aggressive for the motherboard
to handle.Adding more sticks adds to the memory controller load which in this case is on the
motherboard,rather then integrated (Newer Intel cpus,and all AMD cpu since 2004 )

Check that these are correct:
Timings
Voltage (RAM, and MCH)
Correct installation order for the ram sticks (on some boards it's one next to the other,on the
others you skip one (out of 4) slots.

edit*
http://forum.msi.com.tw/index.php?topic=111104.0



1. Start with 2gb of RAM only and install the two hotfixes I already mentioned, turn off you system, unplug main A/C power cable from PSU, put in the additional two modules, clear CMOS after that and try to boot. See if there is any difference.

2. If the problem persists, use 2GB of RAM and update your BIOS to the latest Version under stable conditions. Use the Forum Flashing Tool to update your BIOS. It can be found here:

http://forum-en.msi.com/index.php?topic=108079.0

Read the at the end of that thread as well regarding SureHands Live Update:

http://forum-en.msi.com/index.php?topic ... #msg826609

3. After Flashing the BIOS, clear CMOS again and see what happens if you put in 4Gb of RAM.

4. If the problem persists, try to manually set DRAM frequency to 533 MHz for testing and try again.