Win7, 64-bit -> can't install 8-Gb DDR2?

Thanks, but they are 2GB each: F2-5300CL4D-4GBPQ =>
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231120

"G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 667 (PC2 5300) Dual Channel Kit Desktop Memory Model F2-5300CL4D-4GBPQ"

I think that last part of the label is meaning it's a '4-Gb pack'

Update....the increase in voltage wasn't stable, caused the system to shut down after a while. I tried to start it up again, but it wouldn't boot...strange. I tried all kinds of increasing the 4-4-4-12/1.8 volts to 5-5-5-5-12/13/14 @ 1.8, 1.9, 2.0 and still not stable. Of the 4 similar sticks of 2-Gb, I could switch the pairs around in paired placement in either the 1st/3rd or 2nd/4th slots and it would work and switch the sticks around so there was nothing with the individual memory sticks. I finally found I could put 2-Gb sticks in 1st, 3rd, and 4th slots (= 6-Gb) but I couldn't put them in 1st/2nd and 3rd, or 1st/2nd and 4th. So I'm up to 6-Gb....and this is using 667 Mhz, 4-4-4-12 ???, but not able to reach 8-Gb. If anyone has any further suggestions, please let me know.

Thanks for the comments... but I found this tidbit regarding my motherboard (see below). Does this mean the video card memory and other memory requirements will not allow me to have the full 8-Gb of system memory? If so, then why do they even bother to put an 8-Gb allowable system memory number out there if you can't possibly attain that figure? I'm wondering if it will allow me to add 2 more Gb's (to achieve 6-Gb of system memory by adding 2x 1-Gb sticks to the 2x 2-Gb sticks already in there?).
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I found this... does this mean that all this other stuff takes away from system memory, and that even though it says there is an 8-Gb limit, I can't even achieve that because of all these other resources? (I think I just answered my own question?).

2.1 Memory Resources

2.1.1 Addressable Memory

The board utilizes 8 GB of addressable system memory. Typically the address space that is
allocated for PCI Conventional bus add-in cards, PCI Express configuration space, BIOS (firmware hub), and chipset overhead resides above the top of DRAM (total system memory). On a system that has 8 GB of system memory installed, it is not possible to use all of the installed memory due to system address space being allocated for other system critical functions.

These functions include the following:
• BIOS/firmware hub (2 MB)
• Local APIC (19 MB)
• Digital Media Interface (40 MB)
• Front side bus interrupts (17 MB)
• PCI Express configuration space (256 MB)
• MCH base address registers, internal graphics ranges, PCI Express ports (up to 512 MB)
• Memory-mapped I/O that is dynamically allocated for PCI Conventional and PCI Express
add-in cards The board provides the capability to reclaim the physical memory overlapped by the memory mapped I/O logical address space. The board remaps physical memory from the top of usable DRAM boundary to the 4 GB boundary to an equivalent sized logical address range located just above the 4 GB boundary. Figure 16 shows a schematic of the system memory map. All installed system memory can be used when there is no overlap of system addresses.

Rehed21 and Tradesman1, thanks to both of you. You both indicated increasing the voltage (Rehed21 said that twice before Tradesman's post). My Bios allowed changes but had to select from drop down list of 1.8, 1.9, 2.0. So I went up to 1.9, shut down the system, put the two remaining sticks in the Dimm 1 slots and powered it back up....and whereas before it wouldn't even boot, it did so this time....and I checked via Control Panel => System, and it showed up as 8-Gb !!!

This is annoying because I contacted support for both G.Skill (who's memory I am using) and all they could offer was that I had 2 matched sticks purchased as 2 separate 2-packs, suggesting that all 4 were not identical even though I purchased identical settings....the guy there suggested I purchase a quad-pack (4-pack) and that should solve my problem, lol.

Then, I had a web chat with an Intel tech today....and you know it's bad when he says, hold on, let me check this out....and then he references what is says in the MB manual (thanks, but I have that already)... I was looking for some computer-literate tech person, not someone who can look up stuff in the equipment manual.

You guys were spot-on. Thanks. Now just one more question.... my memory is all CL4-4-4-12, but my bios is showing 5-5-5-12. Should I change the "5's" to "4"? or leave well enough alone?

Thanks again.

Thanks... I changed the Bios settings to 4-4-4-12 (instead of 5-5-5-12) to match the memory sticks, and nothing bad happened, it runs!! Thanks again. I've never had these problems before even though I've built about 15 computers.

Also, the Intel tech guy said "that MB is not compatible with Win7", and I had to tell him, gee, I've been using it with Win7 (32-bit) for over 2 years and consider this my most stable system I ever had. I told him I updated to 64-bit and was trying to take advantage of the higher memory allowance and he reminded me that the MB is not compatible with Win7, lol. I can only imagine in the course of a year, how many people this guy must put off in the wrong direction.