Upgrading memory in HP Desktop and confused

Hello, I am needing to upgrade memory on my HP Desktop. Can you please help guide me on what to buy? I went on line and talked live with a HP Tech and gave him my computer SN. I thought I understood what he said and what I needed, until I went to the store today. I got confused by all the choices and person talking way over my head. I have a HP Desktop Pavillion a450y. Running Windows XP Home. It has 512MB/ DDR SDRm, with Cache Ram 1024 Ram, Intel Pent 4 CPU 3.00 GHZ,CPU Speed 3000MHZ/800MHZ. ***** HP Tech gave me the following information about my computer: ****** The computer was shipped with EXCH-DIMM- 512MB PC3200 (DDR) UNBUFFER memory. It has an Oxford-UL6E motherboard and will support maximum memory of 2.0 GB. The specification the RAM that is supported by this motherboard is as follows. 184-pin DDR-DIMMs PC2100 (266 MHz), PC2700 (333MHz) and PC3200 (400 MHz) DDR-SDRAM unbuffered, non-ECC (64-bit) DIMMs Single-sided DIMMS only 2.5 V memory only 2.0 GB maximum memory There are total of 2 RAM slots on the motherboard. The basic specification should be possibly unbuffered and 184-pin DDR-DIMMs. Choose the speed of PC2100 (266 MHz) or PC2700 (333MHz) or PC3200 (400 MHz). Install either another 512 MB RAM , 1 GB on each slots, or 2 GB on one slot. I know I want to at least purchase 1gb and keep the 512mb. (I feel that there is no use throwing away good memory and spending more that I need to) But what do you think??? Does it have to be 184 pin ? and Unbuffered? Single sided? Does it need to be PC3200 or what Mhz do I need ? I printed all this info out, and when I got to the store I was confused. If you could help me and put this a little simpler, I would really appreciate it. Thanks for taking to time to answer!

PC desktop memory is pretty standardized. what you need to know if its DDR or DDR2.
As for the MHZ yours shipped with: PC3200 or DDR400

Choose the speed of PC2100 (266 MHz) or PC2700 (333MHz) or PC3200 (400 MHz).

your board supports all of the above, but i would stick with DDR400 to get the full benefits of the bus.

Does it have to be 184 pin

yes because thats the standard for DDR, DDR2 is 240 pin modules

Unbuffered? Single side

as far as i know, yes and yes.

there are many online memory config. you can use, you might also find it less expensive online:

http://www.crucial.com/
http://www.kingston.com/
http://www.ocztechnology.com/

a good memory guide (PDF):
http://www.kingston.com/tools/UMG/default.asp

Hello, Thanks for the fast reply and advice. The Kingston Tool page really helped me to understand things better also. I think I should be fine with all the info I have, you may close this out. You guys are always great in helping me and everyone out. My donation is in the mail! Best wishes for a great and safe Holiday Season!

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