<s>
A	O
blade	B-Architecture
PC	I-Architecture
is	O
a	O
form	O
of	O
client	O
or	O
personal	B-Device
computer	I-Device
(	O
PC	O
)	O
.	O
</s>
<s>
In	O
conjunction	O
with	O
a	O
client	O
access	O
device	O
(	O
usually	O
a	O
thin	B-Device
client	I-Device
)	O
on	O
a	O
user	O
's	O
desk	O
,	O
the	O
supporting	O
blade	B-Architecture
PC	I-Architecture
is	O
typically	O
housed	O
in	O
a	O
rack	O
enclosure	O
,	O
usually	O
in	O
a	O
datacenter	O
or	O
specialised	O
environment	O
.	O
</s>
<s>
Together	O
,	O
they	O
accomplish	O
many	O
of	O
the	O
same	O
functions	O
of	O
a	O
traditional	O
PC	O
,	O
but	O
they	O
also	O
take	O
advantage	O
of	O
many	O
of	O
the	O
architectural	O
achievements	O
pioneered	O
by	O
blade	B-Architecture
servers	I-Architecture
.	O
</s>
<s>
Like	O
a	O
traditional	O
PC	O
,	O
a	O
blade	B-Architecture
PC	I-Architecture
has	O
a	O
CPU	B-General_Concept
,	O
RAM	B-Architecture
and	O
a	O
hard	B-Device
drive	I-Device
.	O
</s>
<s>
Some	O
can	O
support	O
multiple	O
hard	B-Device
drives	I-Device
.	O
</s>
<s>
Enclosures	O
offered	O
by	O
current	O
blade	B-Architecture
PC	I-Architecture
vendors	O
are	O
similar	O
but	O
not	O
identical	O
.	O
</s>
<s>
Most	O
have	O
moved	O
the	O
power	O
supplies	O
,	O
cooling	O
fans	O
and	O
some	O
management	O
capabilities	O
from	O
the	O
blade	B-Architecture
PC	I-Architecture
to	O
the	O
enclosure	O
.	O
</s>
<s>
Up	O
to	O
14	O
enclosures	O
can	O
be	O
placed	O
in	O
one	O
industry	O
standard	O
42U	B-Application
rack	I-Application
.	O
</s>
<s>
Blade	B-Architecture
PCs	I-Architecture
support	O
one	O
or	O
more	O
common	O
operating	O
systems	O
(	O
for	O
instance	O
Microsoft	O
has	O
created	O
a	O
“	O
blade	B-Architecture
PC	I-Architecture
”	O
version	O
of	O
their	O
XP	O
and	O
Vista	O
Business	O
operating	O
systems	O
and	O
many	O
Linux	O
distributions	O
are	O
installable	O
)	O
.	O
</s>
<s>
This	O
is	O
a	O
major	O
difference	O
from	O
server-based	O
computing	O
,	O
which	O
supports	O
multiple	O
users	O
simultaneously	O
using	O
an	O
application	O
hosted	O
on	O
one	O
discrete	O
server	O
(	O
be	O
it	O
a	O
discrete	O
piece	O
of	O
hardware	O
or	O
a	O
discrete	O
virtual	B-Architecture
machine	I-Architecture
on	O
a	O
server	O
)	O
.	O
</s>
<s>
Access	O
to	O
the	O
device	O
is	O
usually	O
achieved	O
via	O
various	O
Virtual	B-Protocol
Network	I-Protocol
Computing	I-Protocol
(	O
VNC	B-Protocol
)	O
,	O
which	O
allows	O
users	O
to	O
log	O
on	O
to	O
the	O
blade	B-Architecture
PC	I-Architecture
via	O
a	O
client	O
device	O
(	O
usually	O
a	O
thin	B-Device
client	I-Device
)	O
.	O
</s>
<s>
All	O
protocols	O
are	O
negatively	O
impacted	O
by	O
increasing	O
latency	O
between	O
the	O
end	O
user	O
’s	O
access	O
device	O
and	O
the	O
blade	B-Architecture
PC	I-Architecture
.	O
</s>
<s>
One	O
of	O
the	O
biggest	O
challenges	O
the	O
blade	B-Architecture
PC	I-Architecture
vendors	O
have	O
experienced	O
is	O
how	O
to	O
minimize	O
the	O
impact	O
of	O
latency	O
and	O
deliver	O
an	O
end	O
user	O
experience	O
comparable	O
to	O
that	O
offered	O
by	O
a	O
traditional	O
PC	O
,	O
and	O
there	O
has	O
been	O
a	O
number	O
of	O
new	O
entrants	O
in	O
this	O
sub-category	O
of	O
the	O
blade	B-Architecture
PC	I-Architecture
in	O
2007	O
.	O
</s>
<s>
International	O
Data	O
Corporation	O
recognizes	O
blade	B-Architecture
PCs	I-Architecture
as	O
a	O
category	O
separate	O
from	O
other	O
types	O
of	O
PCs	B-Device
and	O
has	O
begun	O
issuing	O
forecasts	O
for	O
blade	B-Architecture
PCs	I-Architecture
.	O
</s>
<s>
ClearCube	B-Protocol
,	O
a	O
small	O
privately	O
held	O
company	O
based	O
in	O
Austin	O
,	O
Texas	O
,	O
gets	O
credit	O
for	O
creating	O
and	O
popularizing	O
the	O
category	O
.	O
</s>
<s>
In	O
contrast	O
to	O
ClearCube	B-Protocol
,	O
HP	O
emphasized	O
density	O
while	O
minimizing	O
power	O
consumption	O
,	O
which	O
resulted	O
in	O
the	O
ability	O
to	O
put	O
far	O
more	O
blade	B-Architecture
PCs	I-Architecture
in	O
an	O
industry	O
standard	O
42U	B-Application
rack	I-Application
(	O
up	O
to	O
280	O
)	O
.	O
</s>
<s>
HP	O
has	O
since	O
migrated	O
to	O
AMD-based	O
blade	B-Architecture
PCs	I-Architecture
.	O
</s>
<s>
Like	O
the	O
other	O
blade	B-Architecture
PC	I-Architecture
vendors	O
,	O
HP	O
offers	O
MS	O
RDP	O
with	O
their	O
solutions	O
,	O
and	O
they	O
have	O
announced	O
availability	O
of	O
another	O
protocol	O
called	O
Remote	B-Application
Graphics	I-Application
Software	I-Application
that	O
has	O
some	O
advantages	O
over	O
MS	O
RDP	O
,	O
especially	O
in	O
regard	O
to	O
delivery	O
of	O
three-dimensional	O
and	O
streaming	O
content	O
.	O
</s>
<s>
Hitachi	O
offers	O
a	O
blade	B-Architecture
PC	I-Architecture
of	O
their	O
own	O
in	O
Japan	O
.	O
</s>
<s>
Though	O
more	O
like	O
the	O
CCI	O
solution	O
than	O
the	O
ClearCube	B-Protocol
solution	O
,	O
it	O
is	O
less	O
dense	O
and	O
has	O
all	O
cabling	O
out	O
of	O
the	O
front	O
of	O
the	O
unit	O
.	O
</s>
<s>
Common	O
value	O
proposition	O
of	O
blade	B-Architecture
PCs	I-Architecture
relative	O
to	O
traditional	O
PCs	B-Device
:	O
</s>
<s>
As	O
an	O
alternative	O
to	O
traditional	O
PCs	B-Device
,	O
the	O
blade	B-Architecture
PC	I-Architecture
solutions	O
offered	O
by	O
the	O
various	O
vendors	O
are	O
effectively	O
competing	O
with	O
PCs	B-Device
,	O
albeit	O
they	O
are	O
based	O
in	O
datacenters	O
.	O
</s>
<s>
Blade	O
workstation	O
:	O
These	O
solutions	O
tend	O
to	O
be	O
much	O
more	O
expensive	O
than	O
the	O
traditional	O
blade	B-Architecture
PCs	I-Architecture
,	O
and	O
befitting	O
their	O
more	O
high-end	O
specs	O
,	O
they	O
are	O
much	O
more	O
capable	O
.	O
</s>
<s>
Virtual	B-Application
PC	I-Application
:	O
Unlike	O
blade	B-Architecture
PCs	I-Architecture
,	O
some	O
vendors	O
of	O
virtualization	O
software	O
(	O
such	O
as	O
ESX	B-Operating_System
from	O
VMware	O
)	O
have	O
recently	O
popularized	O
the	O
idea	O
of	O
using	O
a	O
hypervisor	B-Operating_System
such	O
as	O
ESX	B-Operating_System
to	O
create	O
multiple	O
Virtual	B-Architecture
Machines	I-Architecture
(	O
VM	O
)	O
that	O
sit	O
on	O
top	O
of	O
the	O
hypervisor	B-Operating_System
,	O
and	O
load	O
a	O
client	O
operating	O
system	O
in	O
each	O
VM	O
.	O
</s>
<s>
So	O
unlike	O
the	O
blade	B-Architecture
PC	I-Architecture
solutions	O
described	O
above	O
,	O
in	O
a	O
virtualized	O
model	O
all	O
end	O
users	O
share	O
the	O
underlying	O
hardware	O
resources	O
.	O
</s>
