according to the Emachine website and the number of your computer that you gave T6528
Link
CPU: AMD Athlon™ 64 3500+ processor with AMD 64 Technology
(2.2GHz, 2000MHz system bus, 512KB L2 cache)
Operating System: Genuine Microsoft® Windows® XP Home (SP2)
Chipset: NVIDIA® GeForce® 6100
Memory: 512MB DDR (1 × 512MB), 400MHz (PC3200)
Video: NVIDIA® GeForce® 6100 GPU
Up to 128MB of shared video memory
PCI Express (PCIe x16) slot available
if this is the right information then we can tell you what ram u need
but you say you got 365mbs of Ram but they say you have 512mb (if we add the 128mbs of shared video it only totals 493mbs
so i am not sure if this is your computer or not