Cuando lo tengas instalado (el de 64 bits) puedes probar el mismo comando que te indica redy pero solo para la memoria a ver que es lo que te detecta.
sudo lshw -class memory
Saludos
Jose
siguiendo tu indicación, ejecuto la orden y :
*-firmware
description: BIOS
vendor: American Megatrends Inc.
physical id: 0
version: P1.80
date: 12/10/2007
size: 64KiB
capacity: 448KiB
capabilities: pci pnp upgrade shadowing cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer int10video acpi usb ls120boot zipboot biosbootspecification netboot
*-cache:0
description: L1 cache
physical id: 5
slot: L1-Cache
size: 64KiB
capacity: 64KiB
capabilities: internal write-back data
*-cache:1
description: L2 cache
physical id: 6
slot: L2-Cache
size: 1MiB
capacity: 1MiB
capabilities: internal write-back unified
*-memory
description: System Memory
physical id: e
slot: System board or motherboard
size: 4GiB
*-bank:0
description: DIMM SDRAM Synchronous
product: PartNum0
vendor: Manufacturer0
physical id: 0
serial: SerNum0
slot: DIMM0
size: 2GiB
width: 64 bits
*-bank:1
description: DIMM SDRAM Synchronous
product: PartNum1
vendor: Manufacturer1
physical id: 1
serial: SerNum1
slot: DIMM1
size: 2GiB
width: 64 bits
O sea, dos chips de memoria RAM de 2 Gb cada uno, total 4 Gb, y sistema de 64 bits. Sin embargo, si observo la información de "Detalles" en "Parámetros del sistema", dice:
memoria: 2,8 Gb
Tipo de SO: 64 bits