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Yesterday I installed WIndows 7 Ultimate 64 bit. My computer has 6 GB inside (2x2 GB en 2x1GB) On setup, I got a bluescreen. I remembered from a previous installation that i had to remove half of the memory.

After installation finished I put the extra memory back. I booted windows, but after the message ' windows is loading' the computer rebooted and i was asked if i would like to fix the boot process (i'm not sure what it said, this is just of the top off my mind)

the computer just keeps rebooting, unless I remove the extra 2x1 gb memory. I thought 64 bit was able to handle more than 4 GB? What am I doing wrong?

Update I tried booting to the 640x480 configuration (as I read on a forum), but that too resulted in an instant reboot.

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What motherboard/chipset do you have? Does the nwe memory stick specs match the existing ones ? – Sathya Nov 3 '09 at 14:19
The Interl Processor utility says that I have an Intel Pentium D CPU 820 (2.8 GHZ). I can't find the chipset info, because the utility from Intel is not working in windows 7 – jao Nov 3 '09 at 16:46
up vote 2 down vote accepted

This could be that the memory is dodgy, have you tried using it in another machine to see if it still works,

The same thing happened to me, and it just seems that RAM can damage easily, i have a stick that will crash any computer i stick it in

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i've swapped the memory, but still no luck. the computer boots perfectly when the 2x1 gb are installed, and it also boots happily when the 2x2 gb memory banks are installed. – jao Nov 3 '09 at 13:36
Did you have some other OS on it previously, with all 4 sticks in working fine? – Dmatig Nov 3 '09 at 13:41
I had Win XP 32 bit, which could only handle the first 4GB of memory. – jao Nov 3 '09 at 16:32
If it wont boot, i doesn't sound like its the OS, its more to do with the actual motherboard and BIOS – admintech Nov 3 '09 at 16:43
it probably was the motherboard, but i've upgraded to a new computer since – jao Oct 7 '11 at 13:20

Are the memory modules installed correctly in their slots? Recent motherboards put the memory in Dual Channel mode if 2 similar DIMMs are installed in the right slots.

Due to interleaving, if you have 4 slots (DIMM1, DIMM2, DIMM3, DIMM4) and your 4 memory modules, you must install them this way:

  • DIMM1 : 2 GB
  • DIMM2 : 1 GB
  • DIMM3 : 2 GB
  • DIMM4 : 1 GB

If you install the 2x 1GB modules in slot DIMM1 and DIMM2, they will run correctly in Single Channel mode. But I'm pretty sure it's not recommended (nor even supported) to have the 2GB modules in DIMM1 and DIMM2, and the 1GB modules in DIMM3 and DIMM4.

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