A question for the computer guru's

The RAM sticks in each slot should match; 256/256 or 1 Gb/1 Gb. I don't know anything about your HP laptop but most new models can handle 2 Gb easily.

:yeah: Your manual should tell which combinations and how much RAM it can address. Generally speaking though, you don't mix stick sizes

In that case, is it bad to leave that slot open?

It appears from HP's website that your laptop can use 2 GB of RAM. It will not hurt at all to run with one slot open.

That would, of course, explain why it runs OK with a 1 GB card in one slot. If it could only handle 1 GB total the usual configuration would be one 512 MB card in each slot.

Assuming it is in fact DIMM and not knowing weather or not the motherboard supports Dual Channel memory.

Lets go look. And since when is the Pavilion a laptop? DO you have a specific model number. I'm seeing HP Pavilion dv4000LA HP Pavilion dv4000CTO HP Pavilion dv4000XX and are you sure it's a 4000 and not just a 4000 series?

Please elaborate and I'll get you the answers.

It is a notebook, the question is, is it a 4000 CTO? 4000LA? or 4000XX?

http://search.hp.com/query.html?qt=...omktg&h_audience=hho&h_audiencerestrict=&st=1

Looks to me like the 4000 series all use the same documentation which states'

The notebook has one memory module compartment, located on
the bottom of the notebook.
You can increase the amount of RAM (random access memory)
in the notebook with an approved optional memory module.
Each notebook memory module slot supports one 256-MB,
512-MB, 1024-MB, or 2048-MB DDR2 SODIMM memory
module.
Some notebook models are shipped with one of the 2 memory
module slots vacant. On other models the memory module slot
may contain a preinstalled memory module that can be replaced
at any time.

Click to expand...

Comps are smart, toss both those RAM sticks in there.

You won't be running Dual Channel regardless on 1 stick or with both in so why not give your system a littel extra memory. It'll help with multi-tasking and photoshopping! [granted not much.]

If either stick isn't compatible with the mobo you'll see it the moment you boot it. But if you wanna really see if its stable you can just run Memtest86 on it a few times.

It will let you know if it recognizes both sticks...I havemixed RAM many times with no problems. After loading both go to System properties and see what it says you have. if you only see one gig its not recognizing it. Would run better matching but not a must.....this is advice from tried and succeeded many times over.

I honestly have no idea what series type it is.... The most it says on the laptop itself is dv4000.... hmmm....

I really appreciate you guys finding all this information for me though! Thanks!

I've come to learn from OEM vendors that whenever a model/series has the exact name aside a different ending they are usually built of the same motherboard. The difference will usually be the processor and accessories.

What I mean is I had a Gateway Solo 9500 CL and they had a 9500 XL/DL and I beleve a XE. The difference between them as I learned was that the XL/DL brought more RAM stock and a faster processor [if you ever do those "Customize things" you understand what I mean] amd the XE was their top o line model with that brought the works stock.

So when I had to look stuff up for mine those models all shared the same manual and drivers page. The 9550 was just the same model with Windows XP (this is when Windows XP had just come out.)

So like Pinball said just toss the sticks in there. The comp will tell you what it likes and doesn't like. I've run weird combinations of RAM in the past myself.

Kev, That's the one I read too but I didn't read all of them to see if they were the same. Either way, performance wise we're talking about DIMMs and not SIMMs. So it doesn't really matter weather you have 1 or 2 in there. The empty slot doesn't hurt anything at all.

If the system supported Dual Channel memory it would be a different story. In that scenario you would run matched pairs to put the system into Dual Channel mode. Running mixed modules or a single module disables Dual Channel mode but i don't think that system supports it anyway.

Did we help you?

Oh I didn't read all these new posts. Yes if you're not going to get Dual Channel anyway then stick it all in there. If it works you have some extra memory but the system only supports up to 2 GB