Each of your two memory slots can hold DDR2 PC2-5300, DDR2 PC2-6400 with a maximum of 2GB per slot. However, unless you use a 64-bit operating system, only 3.5GB will be recognized.
Please post back and let me know if you need more help.
Thank you for your Help!
Ok for the PC-5300.
Are you sure about DDR2-6400 ?
The motherboard optiplex GX520 suports the PC2-6400 or the PC2-4200 ?
PC2-4200 is not fast enough for some of the supported processors FSB.
Faster Ram does not hurt anything but it may not run at the fastest speed unless the processor is also running at the top speed for the FSB.
Can I use 4GB (2x2GB) PC3-8500 DDR3 1066MHZ NON ECC in my Dell Optiplex GX-520? I know the 533Mhz and the 800MHz work, but not sure about this one.
My only concern is if this memory work.
I can confirm that this memory will not work with the system as the system takes 400Mhz and 533MHz DDR-2 DRAMs, but the memory you have listed is DDR-3. DDR-3 memory will not fit in the memory slots in the Optiplex GX520.
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You can but not all brands will work. If your processor has 800mhz FSB then you need PC-2 6400 Ram.
Memory Type: DDR2 PC2-5300, DDR2 PC2-6400, DDR2 (non-ECC)
Maximum Memory: 4GB
Each memory slot can hold DDR2 PC2-5300, DDR2 PC2-6400 with a maximum of 2GB per slot.*
*Not to exceed manufacturer supported memory.
I also have a Dell Optiplex GX520. I recently installed 4 GB of memory (using 4 GB (2x2 GB) G.Skill DDR2 PC2-6400 DIMMs). However, even though I am using windows 7 (64-bit), the total physical memory is only 3.5 GB. When I check the memory in the BIOS (version A11) it reports two 2 GB DIMMS. Is this because some memory is reserved for the video card? Or is there another reason? That is, is the chipset (i945G) limited to 3.5 GB somehow?