Hardware Reference
In-Depth Information
is limiting module capacity, updating the BIOS may allow the system
to recognize the larger memory modules. If the chipset is limiting
module capacity, there's no fix.
Note that the maximum memory module capacity (and the maxi-
mum overall memory) supported by a motherboard may depend
on the number of memory slots occupied and/or the speed of that
memory. For example, a particular motherboard may support 8 GB of
total memory in the form of two 4 GB modules, but not in the form
of four 2 GB modules. Similarly, a motherboard may allow all four of
its memory slots to be populated with slower memory, but only two
slots with faster memory.
Before you purchase a motherboard, make sure it supports the spe-
cific memory configuration you want to use. Check the detailed
motherboard specifications web page and also use one or more of
the memory configurator pages provided by Crucial, Kingston, and
other memory vendors.
Expansion slots
Most motherboards include expansion slots, which you can populate with
expansion cards to provide functions that the motherboard does not. For
example, if you purchase a motherboard that provides only USB 2.0 com-
munication ports, you can later upgrade your system by installing a USB
3.0 expansion card. Most current motherboards provide some mix of PCI
and PCI Express (PCIe) slots.
PCI
The older PCI standard defines one specific set of physical and elec-
tronic requirements for a PCI expansion slot, so any current PCI ex-
pansion card can be used in any current PCI slot (assuming that the
case puts no constraints on the physical height or length of the card).
In June 2010, Intel announced that it was retiring the PCI specifica-
tion in favor of PCI Express. PCI expansion cards and motherboards
with PCI slots are likely to remain available for some time to come, but
development of new PCI products has now largely ended, and future
products will all be PCI Express.
PCI Express
The newer PCIe standard defines the physical and electronic charac-
teristics of a connector that may be used individually (called PCIe 1x)
or may be concatenated into a single combined 4x, 8x, or 16x PCIe
connector to provide correspondingly higher bandwidth.
PCI Express is now used universally for video adapter cards, but as
of mid-2010 PCI expansion cards still greatly outnumber PCI Express
expansion cards, despite the fact that PCI Express is superior and has
been available for years. Until now, most expansion card makers have
adopted an if-it-ain't-broke-don't-fix-it attitude. With Intel's depreca-
tion of the PCI standard, we expect that to change, with more and
