BleepingComputer.com: Upgrading Memory 2gb to 4gb

Hi All,

I did a search for this already on this site and others, but to no avail, I cannot figure this out.

Problem:
PC will not start up or POST when adding new memory but when replacing the memory with the old RAM, boots just fine

Details:
Old RAM total of 2GB: G.Skill 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Model F2-6400CL5D-2GBNQ
New RAM total of 4GB: G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Model F2-6400CL5D-4GBPQ

Computer Hardware and O/S
Motherboard: ASUS P5K-e
CPU: Intel Core 2 Quad Q9300 2.5GHz
PSU: CORSAIR CMPSU-750TX
GPU: EVGA GeForce GTX 460 (Fermi)
CASE: Antec 900
WinXP(32bit)

As you can see the RAM is exactly the same speed and board can support up to 1066, but just wanted to replace the RAM with the same speed etc. They are in the correct slots etc so I am just totally clueless. So before I return the RAM and try 2 (2 x 1GBs) I thought I would try here.

Thanks in advance,
Chris

P.S. Does anyone know a solution to getting 8GB on a 32 bit O/S? Or is the only option to either upgrade to 64bit or go Win 7?

the only way to get your computer to recognize more then about 3.5 gig of ram is to upgrade to a 64 bit operating system. Be warned, windows 7 also comes in 32 bit, so if you upgrade keep an eye on that. As for your memory, I would boot up with the old memory and check the voltage in the BIOS. they both should be the same-between 1.8-1.9v according to the manufacturers spec-but good to double check. I would then check the new ones by putting them in one at a time, and seeing if its just a defective module. If they still dont work, I would recomend RMAing them.

Here's the reason why a 32-bit operating system can't see 4GB of RAM.

A 32-bit operating system has an Address Space of 4GB. This space is not only used for the RAM, but for other critical functions such as the system BIOS, motherboard resources, memory mapped I/O, AGP, PCI, PCI-E, and other memory allocations for PCI devices use this space as well.

Different onboard devices and different add-on cards (devices) will result in different total memory size. This means that the more PCI cards installed will require more memory resources, resulting of less memory free for other uses, like RAM. Typically a 32-bit operating system will recognize between 3.3GB and 3.5GB of total RAM.

Like the_patriot09 suggested, please insert the RAM modules one by one, to rule out the defective one.

Spec wise, both kits are exactly the same (timing & volt), save the bump in memory capacity.