Question for the memory experts...

i have been out of the states for a really long time, living on tropical islands where tech news isn't exactly the top subject. so i am coming back to the states for a visit, and wondered if anyone can give me some information about memory?
for instance, what is the largest memory chip you can purchase? can i purchase a 2 gig, 4 gig or maybe even a six gig chip? and can you get it for a laptop? what is the fastest memory you can put in a laptop right now? how expensive is memory right now? i know it goes up and down pretty quickly, at least it did the last time i lived in the states.
thanks for any information anyone can share. i appreciate it.

over 20 views and nobody has any information on this? just looking for a few simple answers...


New Member
The answers aren't simple.

Most laptops use SODIMMs (small outline dual inline memory modules). Depending on the age of the laptop, it could be SDRAM (synchronous dynamic random access memory), DDR (double date rate), DDR2 (newer type of DDR), or DDR3 (newer, not yet common in laptops, I think). The type and maximum capacity will be specific to your laptop.

For desktops, DIMMs come in similar types, physically incompatible with SODIMMs. Newer machines run DDR3. I believe that 4GB DDR3 DIMMS are just coming to market now. (By that I mean regular DDR3. Buffered RAM has been available longer, but most people don't have motherboards that can use buffered RAM.) Some machines from the early 2000s used Rambus memory, which seems to have been a technological dead end.

If you're looking to buy RAM in the US for a specific machine, go to or They have memory configurators that'll tell you what's currently available for your system.

Does this have any connection with Windows 7?

i have a hp pavilion dv9700, and it is less than two years old. i am running a core 2 duo, 2.6 ghz., with three gig's of ram, and was just curious about upgrading when i come home.


New Member
OK, but this still doesn't sound very Windows 7 - ish.

According to HP, your dv9700 has two RAM slots, for PC2-5300 (DDR2) SODIMMs. The largest stick it supports is 2GB, and the maximum total memory is 4GB. (Some systems don't permit you to fill every slot with the largest supported stick, but that's not a problem here.)

I doubt that going from 3GB to 4 is a worthwhile upgrade. If you decide to do it anyway, see here, for example:

Computer memory upgrades for HP - Compaq Pavilion dv9700 CTO Laptop/Notebook from

(I'm not sure that this is your exact model, but it may not matter.) The good news is that a 4GB kit costs about $56. The PC2-6400 are also listed as compatible, although they will probably run at PC2-5300 frequencies.

4GB SODIMMs exist, but they aren't listed as compatible, and they are much more expensive (hundreds of dollars for an 8GB kit).

If you want 4GB or more of RAM, I suggest a web search on the limitations of 32 bit Windows operating systems. (The short answer is that you'd need a 64 bit OS to fully use 4GB or more of RAM.) You may need a different laptop PC to install more than 4GB, regardless. The fastest Intel CPU that I see in the manual for your system is a Core2 Duo T770, which is 64 bit capable. (On the other hand, it's listed at 2.4 GHz. You wrote 2.6 GHz. What've you got?)

i have a t9500 2.6 ghz, and it is a 64 bit processor. i am running win 7 x64. thanks so much for all of your research. i looked around but didn't find all of that. so of the two below, which is the faster ram?
the second one has a lower CL, which they say is faster, but the first one is pc2-6400, which i would guess is faster. so what is your opinion?

4GB kit (2GBx2)
Part #: CT782314 • DDR2 PC2-6400 • CL=6 • Unbuffered • NON-ECC • DDR2-800 • 1.8V • 256Meg x 64 • • more details

4GB kit (2GBx2)
Part #: CT782325 • DDR2 PC2-5300 • CL=5 • Unbuffered • NON-ECC • DDR2-667 • 1.8V • 256Meg x 64 • • more details

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New Member
I don't know which would be faster in practice for a laptop.

On a desktop system with the RAM timings and frequencies configurable in the BIOS settings, I'd suggest buying the highest data rate available. The CAS latency (CL) is an issue, but I don't know of a straightforward way of estimating which is faster. I think it's probably application dependent: applications that stream large blocks of data would benefit from high data rates, while applications that use lots of small random data accesses would benefit from low latency.

That's probably irrelevant to most laptops. I doubt that laptops permit adjusting the RAM settings. I've downloaded a service manual for the series of notebooks that may contain yours. (It doesn't mention the T9500 CPU, though, so I'm not certain that it's quite the right one.) I'm not sure whether the dv9700 uses the SPD (serial presence detect) chip on the RAM to set the memory timings, or simply uses fixed values. It's possible that both memory kits would run at exactly the same settings in the dv9700. (Sometimes RAM can be run at a lower CL if it's also run at a lower frequency.)

Sorry that I can't be more definite. My own laptop is a cheap (<$400US) HP/Compaq CQ105NR with very few BIOS settings available. Most of my consideration of RAM was for my desktop, which uses an Asus P6T deluxe mainboard. (I'm using all 6 memory slots, so memory settings are fairly critical.)


New Member
Not to Change the Subject but....

I think your bang for the buck would be in a motherboard upgrade with a quad core duo. In the process you would probably have access to more than 4 gig of ram (you're limited to 4 now) and faster ram at that. With a laptop that might be a big deal however.

You would also pick up a faster front-side bus which would help your over all performance. Chances are you could transfer almost all of your add-ons (HD's, DVD R/W, etc.)

I don't know whether you know someone who could do a motherboard upgrade in your situation.

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New Member
I don't wish to be a nattering nabob of negativism, but a motherboard upgrade for an HP notebook? Do you know anyone who has done one? I hope that someone will correct me if I'm mistaken, but I believe that this is essentially an impossible suggestion.

For example: the OP's T9500 CPU is rated at a max. TDP of 35W. That's quite a bit for a notebook.

A Q9550 is rated at 95W.

I wouldn't object to diverting the thread to a discussion of RAM for desktop systems, but I'm unsure whether the OP would be interested.

Stevae, as far as I've seen so far the max amount is 4 Gb for laptops and 16 Gb for desktops, but not for all as it depends on how much and what type your mb can handle. Important thing not to forget is that a x32 bit OS can use no more than 3,3 Gb, so if you go for 4 or 8 Gb you'll need a x64 bit OS.

Stevae, as far as I've seen so far the max amount is 4 Gb for laptops and 16 Gb for desktops, but not for all as it depends on how much and what type your mb can handle. Important thing not to forget is that a x32 bit OS can use no more than 3,3 Gb, so if you go for 4 or 8 Gb you'll need a x64 bit OS.
From the OP:

" i am running win 7 x64"

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