Memory installation my pc came with 2x512mb of memory i added 2x1gb memory to empty slots but my pc would not work- i took out the 2x512mb and put the 2x1gb into the 1st 2 slots and it works fine can you tell me why it would not work with the 2x512 and 2x1gb in together

I'm a bit confused....did you have all four of these in the ACER and are trying to put the 2x1GB into the Emachine? And that the 2x1 GB wouldn't work in the Emachine but they did in the ACER and that the 2x512 Acer cards worked in the emachine?

If that is what happened here is my best guess. The ACER MOBO will support 533/667/800 MHZ DDR2 RAM. The Emachine will only support 533 RAM. Iys possible the 2x1GB are either 667 or 800 MHZ and are not compatible with the Emachine but will work in the ACER.

you have to use either slots as not the same memory slots

You can upgrade it to 2GB (MAX) if Memory Type: DDR2 PC2-5300, DDR2 (non-ECC)
Maximum Memory: 2GB
Slots: 2
Each memory slot can hold DDR2 PC2-5300 with a maximum of 1GB per slot.

Hope this helps.

There is no reset just because you added memory.

If you have 2- 1GB sticks, try both , one at a time.

Your system spec's and manual tell nothing which dimm banks are suppose to be used , and if you can install 2-1GB sticks,
all it says is it can handle 2GB.

Now it says 512MB, sticks, this could mean you can only use 4-512MB sticks to get too 2GB,.

Now it does not tell which dimms are used if you have 2-1GB sticks,

You have 4 slots, the first two and the second two, most times, you either use the second bank of each pair, or the first slot of each pair,
but as I said, your system does not say.

So you can try both ways and see if one of them work.

Sorry I can't be of more help,but you system has a poor manual
on memory placement.

the memory that you Upgrade doesn't support to your motherboard..

it is better to use a 3200/1gb...

Some of the motherboard DIMMS got limitation. U need to check back the manual. Cannot simply insert different type of speed and capacity on each DIMMs.

check, if you motherboard support 2GB, or else start windows in safe mode with 2GB.

The read speed of your new memory is not compatible with your motherboard. It is a higher rate than allowed. The reason why it works when you have one of your old chips installed is because your PC will automatically drop the higher rate chip down to the one that is working. The reason it does not drop both new chips down to a suitable rate is because it has nothing to guide it like your compatible chip does. Always check the MHz on RAM chips and compare that with the acceptable rates listed on your motherboard specs. The good news is you can probably sell those chips and have money left over when you find upgraded compatible memory that is sure to be cheaper since it is slower.

Please check the type of RAM you are using.
You must return it to BestBuy and try using a Dell store.
Call Dell Accessories sale and they will be able to give to better options and it wud work too.

Your motherboard supports 533MHz memory modules, no more. If you put anything higher in, it will work, but only at the speed of 533MHz, so there's not much point in aiming any higher. Just make sure what you're buying is a DDR2 533MHz memory module, and it's best to get them in increments of 2. If you have 4 slots on your motherboard, get another 2x512MB modules of RAM. If you're running Windows Vista, it might be worth considering 2x1GB modules. I think that pretty much covers your question, if you have anything else to ask, feel free to reply.