Windows 7, 64 bit, and upgrading RAM

I have a E1505 (6400) and I was running Vista 32 bit with 2 x 1 gb ram. I bought 2 x 2 gb ram, and it caused all sorts of problems. I took the opportunity to upgrade to 64 bit with Windows 7 (clean install), and I reinstalled my 2 x 2 gb of RAM. It seems to be running smoothly so far... But only 3.25 gb is recognized as "usable" in Windows and my BIOS. Does anyone know any settings I need to change or if there is a different BIOS for 64 bit OS's?

I did some googleing and found some recommendations for updating the BIOS if RAM that should be usable is not. However, I'm running the latest BIOS for the E1505, A17, but this is over 2 years old.

 

I feel like I've read a ton of threads on this before... officially the E1505 can only support 2GB of memory, so anything strange with 3GB or 4GB is a hard limitation and probably normal. I think K-TRON has the official story on this one...

 

Thanks for the tip, looking through K-tron's stuff it looks like I have a few things to try.

Does anyone else remember Dell offering more RAM when they ordered their E1505? I swear the offered 3 gb, maybe even 4 gb. Anyway, hopefully Windows 7 stays stable with the 3.25 gb. I'm happy with the speed and would like the extra but its not that important.

 

Also, just doing a little research here, but the theory about the chipset being 32-bit and limiting the available memory doesn't check out.

I believe we have Intel 945GM and 945PM (same as GM but without integrated graphics). I need confirmation on this though. However, I am sure, that Intel lists this chipset, as:
• Maximum Memory supported: up to 4 GB at 400, 533 and 667 MHz
• 64-bit wide per channel
(from pg 23, http://www.intel.com/Assets/PDF/datasheet/309219.pdf)

However, they also say:
• 256-Mb, 512-Mb and 1-Gb memory technologies supported
so this may be what is tripping us up.

 

This is correct. The 945 chipset(s) on their own do support 4GB of memory. I'm fairly certain there are other 945 Dell machines that work fine with 4GB. The limitation is most likely in Dell's BIOS or some strange component implementation on the 6400 motherboard.

 

Yep you are limited by the mother board thats why I bought a new 1555
you can have up to 8gb and soon ( 2 years ) it will seem too small, you can easily have 16gb with Win 7, Why they have done this?

Honestly I think money, all the laptop makers do this, makes you upgrade the laptop every 24 to 36 months. Cheeky huh?

 

Orrr.... technology is always evolving. Google Moore's Law.