Problems installing new memory module 1

[yorkshirepudding]

I have a HP Pavillion a1128uk it has 4 memory slots 2 taken up by 2x 256mb modules i bought a single 512 mb module to take it to a Gig of ram.

after installing the new module in the 3rd empty slot the 2nd slot of memory disapeard and only showed on the 1st and 3rd bank installed with 768mb!

so i tried installing the new module in the 4th empty slot and then both the 2nd and 4th module dissapeard leaving only 256mb!!! LOL

so im a bit befuddled as to whats happened i have the right memory for the system of that im sure, is this a problem that requires identical pairs of memory size? in all banks?

any help would be great because it'd be hard to send back the new memory dont want it to go to waste

 

[stduc]

I am not familiar with that system. The mobo manual may help - you should be able to google one up.

Failing that - try the 512 in the first slot. If it sees that add the others to slots 2 & 3 one at a time.

But your mobo may have restrictions as to which RAM combinations it can handle. In addition your new RAM may be faster than the others and that can cause problems.

 

[RICHINMINN]

Many systems now use dual-channel memory, requiring that 2 RAM modules be installed at a time, using slots 1 and 2, then 3 and 4. If you choose to go with single-channel memory, you must use slots 1 and 3. If the system detects a non-dual-channel configuration (i.e. slot 1 occupied, but not slot 2, or slot 3 occupied but not slot 4, or non-identical memory modules installed in slots 1 and 2, or slots 3 and 4) the system reverts to single-channel mode.

When you installed the single RAM module in slot 3, your system switched to single-channel mode, using only slots 1 and 3, hence the 768M that the system saw. When you moved that module to slot 4, your system again saw this as a single-channel configuration, and looked at slots 1 and 3, and found only the 256MB in slot 1.

Rich (in Minn.)

 

[mainegeek]

yorkshire,
Try with the 256 in slots 1 and 3 and the 512 in slot 2.

 

[yorkshirepudding]

Great how can i get it to work correctly, just try several combinations of where to place the RAM

 

[yorkshirepudding]

this is very infuriating! ive tried every possible combination in he 4 slots and its not working, sometimes it only shows up as one module, sometimes the 512mb module is only half capacity, and when they are installed all together the Rating drops from PC3200 to the next level down

friggin heck whats wrong!

 

[RICHINMINN]

Yorkshirepudding,
If you really, really want to use the 512MB module that you bought, put it in slot 1, and one of the 256MB modules in slot 3. Your system will recognize this as a single-channel configuration, and will look only at slots 1 and 3, and will see the 768MB in those two slots. (You can put the other 256MB module in slot 2 or 4, but the system won't see it, since it's looking only at slots 1 and 3 in single-channel mode. But at least it won't get lost if you store it there.)

Using your system in single-channel memory mode will result in a bit lower (maybe 10% or so?) performance.

The best thing would be to buy another **IDENTICAL** 512MB module, then put the 2 512MB modules in slots 1 and 2, and the original 256MB modules in slots 3 and 4, and the system will see all 4 modules, for a total of 1.5 GB of dual-channel memory. Or you could buy 2 identical 256MB modules (they don't need to be identical to the other 2 256MB modules) and put those in slots 1 and 2, with the original 256MB modules in slots 3 and 4, and your system will see 1GB of dual-channel memory, and you'll have the 512MB module sitting on a shelf.

Rich (in Minn.)

 

[electronicsfreak]

My reccomendation, look at the board and find the name and model number of the motherboard and then look up the manual to it and see what it says about the ram.

 

[RICHINMINN]

The motherboard in your system is an MSI unit, MS-7184. It does support dual-channel memory, which requires that you install identical pairs of PC3200 RAM modules in slots 1 & 2, then 3 & 4. Any departure from this will force the system into single-channel memory operation, and it will behave exactly as you have seen it behave (detecting only the memory in slots 1 and 3).

Check out

http://h10025.www1.hp.com/ewfrf/wc/...oduct=1120282&lang=en&cc=us&docname=c00378480

Rich (in Minn.)

 

[yorkshirepudding]

Guys

thanks for all that it is clear to me now why that happended so im going to do this: buy another 512MB module, make sure its the same and install in this way

<SLOT1> 512
<SLOT2) 256 (origional)
<SLOT3> 512
<SLOT4> 256 (origional)

that should enable dual channel mode and give me a good boost of RAM

thank you very much all!