I need more RAM info help!

[Ebb2012]

Ok im not so good at the hardware side of computers so i need some help. I have a gateway with this kind of memory in 2 128MB chips.

General Description

The Rambus� RIMM� module is a general purpose high-performance memory module suitable for use in a broad range of applications including computer memory, personal computers, workstations, and other applications where high bandwidth and low latency are required.
The Rambus RIMM module consists of 128Mb/144Mb Direct Rambus DRAM devices. These are extremely high-speed CMOS DRAMs organized as 8M words by 16 or 18 bits. The use of Rambus Signaling Level (RSL) technology permits 600 MHz, 711 MHz or 800 MHz transfer rates while using conventional system and board design technologies. RDRAM devices are capable of sustained data transfers at 1.25 ns per two bytes (10ns per 16 bytes).
The RDRAM architecture enables the highest sustained bandwidth for multiple, simultaneous, randomly addressed, memory transactions. The separate control and data buses with independent row and column control yield over 95% bus efficiency. The RDRAM's 32-bank architecture supports up to four simultaneous transactions per device.


Features

High speed 800, 711 and 600MHz RDRAM storage
184 edge connector pads with 1mm pad spacing
Maximum module PCB size : 133.35mm x 31.75mm x 1.27mm(5.25" x 1.25" x 0.05")
Each RDRAM has 32 banks, for a total of 512, 384, 256, 192, or 128 banks on each
256/288MB, 192/216MB, 128/144MB, 96/108MB, or 64/72MB module respectively
Gold plated edge connector pad contacts
Serial Presence Detect(SPD) support
Operates from a 2.5 volt supply (�5%)
Powerdown self refresh modes
Separate Row and Column buses for higher efficiency
�-BGA package type (62 Balls)

Ok, now i wanna go to either 512 or even up to 1g if i can afford it. what do yal suggest. Im looking for value as well as performance. If i can use my old memory i'd like to.

I need to find out what "style" of memory to buy. SD, DRAM, bla bla bla

Thanks !

Ebb