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I have a Toshiba Satellite M645 running Windows 7 64bit Pro. The specification states that this particular machine can use up to 8Gb of RAM.

The specs state the RAM is:

DDR3 1066MHz (PC3 8500)
  • I purchased two 4Gb modules and...
  • Shut down the notebook
  • Removed power cord
  • Removed battery
  • waited 10 seconds...
  • removed and replaced (carefully and grounded) the SODIMMS respectively 2Gb with 4Gb.
  • Replaced battery
  • Plugged notebook back in
  • Windows 7 Freezes on logo screen:

    Starting Windows...

But the logo never appears and it just hangs for a long time... better than 15 minutes and I finally got tired of waiting. This is the ONLY behavior I have been able to get when the 4 Gb memory modules are present.

The BIOS recognizes all 8 Gb (8192 Mb) and the same SODIMMS work in a 64 Linux system without any issues. When I replace the new 4Gb modules with the original 2Gb modules, Windows 7 starts fine.

Please advise.

share|improve this question
Are you able to enter Safe Mode by pressing F8 just before logo screen. Likley have to press F8 frequently after POST – Dave M Dec 13 '12 at 21:09
With the modules installed, try resetting the BIOS to defaults. – Karan Dec 13 '12 at 21:14
I will try both of your suggestions. It will take some time to cycle the process. – Android Addict Dec 13 '12 at 21:17
Okay I reset to bios defaults. No luck. I Also tried to enter safe mode and the boot hung on: Loaded: \WINDOWS\SYSTEM32\DRIVERS\CLASSPNP.SYS – Android Addict Dec 13 '12 at 21:57

It looks like you fall within the Maximum memory amount for your laptop, so that's not the issue.

The most likely problem is bad RAM. Try the modules one at a time and see if they work on their own. If only one works, the other one is bad, in that case you may be able to swap it out on warranty.

share|improve this answer
But they both work in another system. How could one be bad under those circumstances? – Android Addict Dec 13 '12 at 21:10
Did you have both SODIMM's filled with the 2GB or only one? if only one, a bad connector? – Scott Chamberlain Dec 13 '12 at 21:11
I put the SODIMMS (both 4gb) into the Linux system. All 8Gb was recognized and the system ran just fine. If either module were bad, I would think even if the Linux system ran, that only 4Gb would have been recognized. – Android Addict Dec 13 '12 at 21:13
@AndroidAddict Good point. – David Dec 13 '12 at 21:14
@AndroidAddict Maybe try one card in each slot in the laptop? Just to confirm that the slots are not broken? – David Dec 13 '12 at 21:15

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