hi i have a custom built pc and i am looking to upgrade the memory i can go up to 4gig but i have xp so it will only let me have 3gig i already have two 512 in there and i was wondering if i need to buy the same make which is in the pc already my mother board is a lanparty rdx200 cf-dr and i need pc3200 ddr also i have 4 slots two taken up with the 512 whats the best and cheapest option?you dont have to buy the same brand, but its a good idea to look for the same speed memory, or just throw what you have out and buy a 2gb kit, since ram is super cheap these daysNot to be a pain in the a$$, but if you're gonna install more than one stick, its usually a good idea to buy a "kit". I'm always hearing about people who install DIFF. brands at diff. times and end up with problems.personally, i would save up enough for a new CPU, motherboard, and RAM. DDR 333 RAM costs about as much as DDR2 1066 RAM. to me, its not worth spending money on old technology, especially when it costs the same, if not more, then new technology.Good point.1.  Motherboard.  Diamond Flower (DFI) LANPARTY UT RDX200 CF-DR ?

2.  The "Crucial" web site www.crucial.com will answer most of your questions.  The following link discusses memory for what may be your motherboard.  Read it and any supporting information very carefully.  And then ask here if there are things you don't understand.

3.  Make.  No you don't have to buy the same "make" as is already in there.

4.  Cost.  I would never buy the "cheapest" memory.  You need it to work without error all the time (not most of the time).

5.  From the referenced link:

QUOTE

    *  USB Support:   2.x Compliant
    * Error DETECTION Support:   Non-ECC only
    * Chipset:   ATI Radeon XPRESS 200 CrossFire
    * Supported DRAM Types:   DDR SDRAM only
    * Module Types Supported:   Unbuffered only
    * Max Unbuffered DDR SDRAM:   4096MB
    * Max Component Density:   512
    * 184-pin DIMM Banking:   4 (2 banks of 2)
    * Graphics Support:   Dual PCI Express x16, CrossFire capable
    * Although the memory can be installed one module at a time, the best performance comes from using matched pairs of modules.

Q: Will my system recognize the maximum upgrade?

A: Possibly

How much memory your Windows OS will recognize depends on which version of Windows you are running. 32-bit versions of Windows will see (and utilize) only 3GB or 3.5GB. To utilize more memory, install a 64-bit version of your OS. More information about OS memory maximums can be found at http://www.crucial.com/kb/answer.aspx?qid=4251.

Q: What memory goes into my computer, and will a FASTER speed be backward-compatible?

A: DDR memory with support for DDR PC2700,DDR PC3200 speeds.

Because DDR memory is backward-compatible, you can safely upgrade your system with any of the guaranteed-compatible DDR speeds listed below, even if your manual calls for PC1600 or PC2100 speeds.

Q: How much memory can my computer handle?

A: 4096MB.

Adding the maximum amount of memory will improve performance and help extend the useful life of your system as you run increasingly demanding software applications in the future.

Q: Do I have to install matching pairs?

A: Yes.

Your system requires that you install memory in pairs.

Q: Does my computer support dual-channel memory?

A: Yes.

To benefit from the performance advantages offered by dual-channel systems, you should install memory in identical pairs. Installing a kitted pair is the best way to ensure that your modules are identical, right down to the chip count.

Q: Does my computer support ECC memory?

A: Yes.

Your system supports ECC. You can put non-ECC modules into an ECC system, but be sure not to mix ECC and non-ECC modules WITHIN a system. Install the same type of modules that are already in your system.