What's the biggest bottleneck of a PC ?

[helloguy]

is it CPU ? RAM ? HDD ?

 

[Elledan]

HDD. A FDD isn't a required part of a PC, so that one doesn't count.

In general, it's the CPU which is the fastest.

 

[Rand]

Well it depends upon what specifically your doing with the PC, but in general I'd say the HDD as it's the slowest piece of hardware in the PC.
RAM I would say can potentially be the second largest limiting factor.
A lack of RAM can drag even the most powerful of processors to it's knees whereas a loads of RAM can make even a relatively weak system seem bearable.

 

[Amused]

<< Well it depends upon what specifically your doing with the PC, but in general I'd say the HDD as it's the slowest piece of hardware in the PC. >>



Second this. I am SO tempted to get an X-15 36 gigger as a boot/application drive, but right now I'm using RAID-0 and it's STILL not fast enough.

Using a laptop drives me crazy. Even though one may have 1 Ghz and 512 RAM, it seems slow as snot with a 4500 or 5400 RPM HDD.

I can't wait until HDDs become solid state.

 

[helloguy]

hmm...so even u've got the fastest hdd say 15k rpm scsi 320mb/s and its still not fast enough?

 

[Snapster]

Judging by the fact that a HDD is the only part that in frequent operation in your computer that is measured in milliseconds, rather than micro/nanoseconds it would have to be that. This is because of the physically moving parts it has.

For parts like CPU/Memory. It's a fine balance between memory and CPU that would be the biggest bottleneck in a PC as both directly affect each other.

 

[Rand]

<< hmm...so even u've got the fastest hdd say 15k rpm scsi 320mb/s and its still not fast enough? >>



Consider how powerful modern processors are, and the capabilities of modern graphics cards, the sheer bandwdith available from modern main memory subsystems..... and then consider the fact that even the fastest 15,000RPM U320 SCSI HDD's available today are capable of a mere 60.5MB/s sustained transfer rates at best.

There is an incredibly dramatic difference between that and even old EDO DRAM, which in turn is ridiculously slow compared to modern processors.

It's akin to comparing the speed of a snail to a puma....

 

[helloguy]

<<

<< hmm...so even u've got the fastest hdd say 15k rpm scsi 320mb/s and its still not fast enough? >>



Consider how powerful modern processors are, and the capabilities of modern graphics cards, the sheer bandwdith available from modern main memory subsystems..... and then consider the fact that even the fastest 15,000RPM U320 SCSI HDD's available today are capable of a mere 60.5MB/s sustained transfer rates at best.

There is an incredibly dramatic difference between that and even old EDO DRAM, which in turn is ridiculously slow compared to modern processors.

It's akin to comparing the speed of a snail to a puma.... >>



oh...okie,i got the picture now..thanks

 

[Wolfsraider]

here


<< Lets face it, the hard drive is the slowest part of a personal computer. With access times around 8 milliseconds, it takes the computer 1000 times longer to access the hard disk than RAM. While the G4 ships with ATA66 and boasts of 66 MBps throughput, it rarely breaks 35-40 MBps. >>





<< Why SCSI? Ultra320 SCSI is almost ready for consumer use. That's a potential 320 megabytes per second. I realize that today's drives aren't quite capable of those speeds, but 15,000 rpm drives are available with access times under 4 milliseconds. >>



here
shows a single x15 36lp harddrives throughput

here

this shows raided benchmarks between a adaptec 3210s and a mylex 352 using 8 drives and a raid 5 array which is not revelant to a non server enviroment such as gaming but cool to see

here

look at the graph at the bottom of this page to see the projected scsi performance vs ide

what i take from this is 4 ide drives in raid 0 are faster than two drives scsi according to this PROJECTED graph but that doesn't by any means take scsi out of the picture it just means you can get scsi speeds at a lower cost

but there is a much bigger reason to go scsi vs ide

SCSI is an interface that can perform data transfers with no requirement from the host CPU. SCSI is multi-tasking. An initiator can issue a command to a target. The target can then disconnect from the bus to perform the task and free the bus up for another task. This is referred to as Connect/Disconnect. Ultra 160 SCSI can have up to 15 devices connected to the bus (30 for a dual channel) and they can be any SCSI device including hard drives, CD-RW?s, scanners, printers, etc. The number of devices can be substantially increased by Logical Unit Numbers. EIDE can have two internal drives connected. Your PC probably has two EIDE buses, so it may have up to four peripherals. Ultra 160 SCSI allows up to 12 m (40 ft) of cabling, which may be internal or external to the computer. For point to point applications, you may have up to 25 m (82 ft) of cable. EIDE is for internal cabling only and the maximum cable length is only 18 inches. Moreover, do not forget that 160 Mbytes/sec is much faster than any EIDE bus

another good read

here

but nowhere have i found the numbers for a 32 bit pci bus using two or more x15 36lp drives and their effects on the pci bus so i am left to assume that it wouldn't be cost effective or that maxing out the pci bus (32 bit) is a real possibility

these are my takes on this and as such may be completely wrong so please as with any information get confirmation before holding any/all information as fact

hope this helps