Difference between 'su' and 'su -' or 'su root' and 'su -root'

“su” is equivalent to “su root” and “su -” equivalent to “su – root”. “su root” is the default command for “su”. That is, if you type “su” it will assume you mean “su root”. To su to another user you will have to add the users name, such as “su username”. If you use “su” you will still have the same environment, for example the $PATH variable, as the user who su’d. If you use “su”, you will have the environment of the user you su’d to.

The diff between “su” and “su -” is “su -” you log in as a root with the env setting/profile (i.e you really log in as a root). Just type “pwd” and you will be in the root home dir @ /root. if you “su” only then basically you just “borrow” the root permission without having all the root env setting/profile. Just “su” from your home dir and type “pwd”, you can see that you still in the user dir i.e /home/username.

They’re just different paths to get to the same destination. “su” is short for super user. You’ll use it when you’re logged in as a user and wish to do something that requires root privileges. Using “su” or sudo is the only way to access root privileges while logged in as a user unless one wishes to reboot and log in as root. sudo is nothing more than another path to becoming a super user.

Here is a small demo:

A good reason to log in as root would be to set up a user account so you don’t have to log in as root. It’s just to make things easier for a person to run as user instead of root yet provide an easy way to access root when needed.

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Intel Core i5 vs Core 2 Duo Comparison- The Difference

This post explains the Difference Between Intel Core i5 and the Core 2 Duo processors.

The Intel Core i5 series is based on two architectures:
1. Westmere (Core i5 6xx – Clarkdale – 32 nm – Dual Core)
2. Nehalem (Core i5 7xx – Lynnfield – 45 nm – Quad core)

Intel Core 2 Duo

Codenamed: Conroe, Allendale, Wolfdale – Core 2

Fabrication: 65 nm / 45 nm

Instruction set: X86, X86-64, MMX, SSE 4.1

Socket: LGA 775

Bus: 1333 MHz FSB

RAM: DDR2

Chipset Support: 965, P3x, G3x, P45, X48

Intel Core i5

Codenamed: Lynnfield, Clarkdale

Fabrication: 45 nm, 32 nm

Instruction set: X86, X86-64, MMX, SSE 4.2

Socket: LGA 1156

Bus: Direct Media Interface

RAM: DDR3

Chipset Support: P55, H55, H57, Q57

LGA 1156, Direct Media Interface, Smart Cache

Like the Intel Core i3 processors, The Core i5 are also native dual cores; they have both processors on the same die which leads to better processing speeds. The quadcore Core i5 processors are native Quad cores – 4 processors on the same die – much faster than two dual cores stitched together. While the Intel Core 2 Duo processors work on the LGA 775 socket, the new Core i3 and Core i5 processors use the LGA 1156 socket and support motherboards based on the following chipsets - P55, H55, H57, Q57.

All the Core i5 processors sport the DMI (Direct Media Interface) which is much faster than the FSB used in Core 2 Duo processors but is not as fast as Quick Path Interconnect in the Core i7. They also have a on die memory controller which helps in much faster memory access than the Core 2 Duo processors. They also support Smart Cache which allows cache memory sharing between the two cores reducing memory latencies.

Difference between dualcore Core i5 and quadcore Core i5 Processors

Like the Core i3 processors, the dualcore Core i5 processors also have a 32 nmfabrication, they are much more power efficient and run faster than Core 2 Duo processors which have a 65 / 45 nm fabrication. There are 5 dual core Core i5 processors (Core i5 6xx) with clock speeds ranging from (Core i5 650) 3.2 GHz to (Core i5 680) 3.6 GHz. They have 2×256 KB L2 cache and 4 MB L3 cache. They also have an on die graphics processor for better graphics performance like the Core i3 series. They also support Hyperthreading enabling 2×2=4 virtual cores.

The quadcore Core i5 processors (Core i5 7xx) have a 45 nm fabrication, and like the Core i7 processors, are based on the Nehalem architecture. There are 2 of them – Core i5 750 (2.66 GHz) and Core i5 750S (2.4 GHz). They have 4 x 256 KB L2 cache and 8 MB L3 cache. They don’t have an on die graphics processor. Also, Hyperthreading is disabled in quadcore Core i5s.

The Core i5 processors are meant for those who need more power than Core i3 processors. The Core i5 650 offers excellent value for money in a gaming rig.

Dual Core Intel Core i5 Prices
Core i5 650 – $176
Core i5 660 – $196
Core i5 661 – $196
Core i5 670 – $284
Core i5 680 – $294

Quad Core Intel Core i5 Prices
Core i5 750 – $196
Core i5 750S – $259

Price list Intel 2nd gen. core i5 processor 


Intel Core i3 vs Core i5 vs Core i7 – The Difference
Intel Core i7 vs Intel Core 2 Duo – The Difference
Intel Core i5 vs Intel Core 2 Duo – The Difference
Intel Core i3 vs Intel Core 2 Duo – The Difference

Intel Core i3 vs Intel Core 2 Duo Comparison- The Difference

This post explains the Difference Between the Intel Core i3 and Core 2 Duo processors.

Just like the Intel Core i7, the Core i3 is based on a new architecture – Clarkdale which is based on the new Westmere microarchitecture. The Intel Core i3 range offers only dual core processors unlike the Core i5 and i7 which offer Quad cores as well.

Intel Core 2 Duo

Codenamed: Conroe, Allendale, Wolfdale – Core 2

Fabrication: 65 nm / 45 nm

Instruction set: X86, X86-64, MMX, SSE 4.1

Socket: LGA 775

Bus: 1333 MHz FSB

RAM: DDR2

Chipset Support: 965, P3x, G3x, P45, X48

Intel Core i3

Codenamed: Clarkdale

Fabrication: 32 nm

Instruction set: X86, X86-64, MMX, SSE 4.2

Socket: LGA 1156

Bus: Direct Media Interface

RAM: DDR3

Chipset Support: P55, H55, H57, Q57

LGA 1156, Direct Media Interface, Smart Cache

Both the Intel Core i3 and Intel Core 2 Duo processors are native dual cores; they have both processors on the same die which leads to better processing speeds. The Intel Core 2 Duo processors work on the LGA 775 socket, the new Core i3 and Core i5 processors use the LGA 1156 socket. The Core i3 processors support motherboards based on the following chipsets – P55, H55, H57, Q57.

As the Core i3 processors have a 32 nm fabrication, they are much more power efficient and run faster than Core 2 Duo processors which have a 65 / 45 nm fabrication. There are two processors in the Core i3 series – Core i3 530 (2.93 GHz) and the Core i3 540 (3.06 GHz). Both have 2 x 256 KB L2 cache and 4 MB of L3 cache. Both the Core i3 processors sport the DMI (Direct Media Interface) which is much faster than the FSB used in Core 2 Duo processors but is not as fast as Quick Path Interconnect in the Core i7.

The Core i3 processors also have a on die graphics processor which offer much better graphics performance. They also support Hyperthreading which means that each core can run 2 threads simultaneously which results in 2×2=4 virtual cores. They also have a on die memory controller which helps in much faster memory access than the Core 2 Duo processors. Also their chipsets are compatible with DDR3 RAM. The whole combination of Core i3 + DDR3 RAM offers much better performance than Core 2 Duo + DDR2 RAM. The Core i3 processors also support Smart Cache which allows cache memory sharing between the two cores reducing memory latencies.

However, unlike the Core i5 and Core i7 processors, the Core i3 processors also don’t support Turbo Boost which allows dynamic overclocking for better performance. Nevertheless, they are priced very low, which makes them a very good deal for budget PCs.

Intel Core i3 i540 – Rs. 4600

Intel Core i3 i550 – Rs. 5100


Intel Core i3 vs Core i5 vs Core i7 – The Difference
Intel Core i7 vs Intel Core 2 Duo – The Difference
Intel Core i5 vs Intel Core 2 Duo – The Difference
Intel Core i3 vs Intel Core 2 Duo – The Difference