What if everything was clocked at 1GHz

[Tesseracted]

What if everything in my PC was clocked at 1GHz. the CPU, the FSB, the PCI slots---Everything. No multipliers. would it run faster than todays 3 GHz Pentiums? What if at 2 GHz. How well would it run?

 

[jhu]

even the harddrive rotational speed?

 

[zsouthboy]

Originally posted by: jhu
even the harddrive rotational speed?

ROFL


We are actually getting to the point at which near everything will be clocked at least 1 ghz... RAM and GPU are the only things i can think of that can actually make it there

 

[Lynx516]

Nope.

The FSB increadibly does not have a huge impact on the number of MIPS a CPU can do.

Due to cache the CPU only goes to RAM 1% of the time. Though 1% still means a few million times a second it does mean that the FSB is not a huge factor in it all. Though it would help.

 

[SuperTool]

Originally posted by: Lynx516
Nope.

The FSB increadibly does not have a huge impact on the number of MIPS a CPU can do.

Due to cache the CPU only goes to RAM 1% of the time. Though 1% still means a few million times a second it does mean that the FSB is not a huge factor in it all. Though it would help.

Actually the memory accesses have a huge effect, because memory latency hasn't improved over the years. It still takes roughly same time from request to data on drams. Now if you have 1% miss rate, and it takes 100 CPU cycles to wait for data, the impact is huge.
The reason the higher FSB doesn't help much is that it only improves throughput, not latency. So if you are loading a small piece of data, you still have to wait 100 cycles for it to get it. The only thing the fsb helps with is that once you wait that 100 cycles you can receive data at a faster rate, but that doesn't matter much unless you are loading a big piece of data.

 

[Mday]

well, recall that everything has a cost.

if everything is clocked at 1GHz, presumably the RAM, FSB and CPU, memory bandwidth intensive calculations will be hell fast. it can be faster than 3GHz parts coupled with existing RAM. for CPU intensive processes, assuming that the clock cycles are used efficiently, the same programs are being used, and the CPUs are the same, then the 3GHz parts will win. now, 2GHz, if everything is at 2GHz, the same benefits exist. but at a lesser cost in terms of raw CPU power.
i would most likely adopt today's 3GHz parts over the everything-1GHz. but everything-2GHz, that i would get.

in terms of what people do, they wont notice much of a difference. in terms of what I do, memory bandwidth will be quite a good thing.

HOWEVER, the bottleneck of the PCI bus still exist, as does the speed of HDDs.

and one more thing, everything-1GHz and everything-2GHz will offer a lot of noise. the extra effort to properly shield everything will probably make it more annoying to deal with.

 

[Lynx516]

Originally posted by: SuperTool

Originally posted by: Lynx516
Nope.

The FSB increadibly does not have a huge impact on the number of MIPS a CPU can do.

Due to cache the CPU only goes to RAM 1% of the time. Though 1% still means a few million times a second it does mean that the FSB is not a huge factor in it all. Though it would help.

Actually the memory accesses have a huge effect, because memory latency hasn't improved over the years. It still takes roughly same time from request to data on drams. Now if you have 1% miss rate, and it takes 100 CPU cycles to wait for data, the impact is huge.
The reason the higher FSB doesn't help much is that it only improves throughput, not latency. So if you are loading a small piece of data, you still have to wait 100 cycles for it to get it. The only thing the fsb helps with is that once you wait that 100 cycles you can receive data at a faster rate, but that doesn't matter much unless you are loading a big piece of data.

Where did I say that memory accesses didnt have a huge effect? I said FSB didnt have a huge effect. Of course latency has the largest effect but their is inherent latencey in the RAM technology which wont allow even lower latencys then seen by teh Opterons. having every thing at 1Ghz wont make a massive improvement except for probably a reduction in latency caused by the increased memmory controller speed as seen in the Opteron. ALso it depends on what ISA you are using. For example an Itanium at 1Ghz slaughters any x86 part wiht ease in most calcuations (talking 2-3x the speed)

 

[Mday]

all the FSB is, is the bus between the CPU and the core chipset. everything else falls under that. purely increasing the FSB wont really help much of anything if the PCI bus is not changed since that will become a source of wasted clock cycles. obviously if you increase the pci bus to the same speed as the fsb, then everything will be that much faster since each other peripheral will have more bandwidth to work with. of course, there will still be wasted clock cycles negotiating the individual devices. however, with such a congested pci bus, increasing the pci bus will definitely help with existing systems. with the fancyful everything-1GHz, the increased fsb will help coupled with the increased pci bus. of course the pci bus is not the only thing that exists which falls under the realm of sources which the can take up the FSB bandwidth. hypertransport, etc, are new methods to decreases wasted clock cycles, or memory cycles. these wasted cycles are what is truly making systems less than spectacular.

the CPU spends a lot of wasted cycles waiting for data, so the goal is not really to make everything fast, since things are fast enough. the goal is to decrease wasted cycles. with everything-1GHz, there should be less wasted bandwidth. however, the CPU is 1/3 the speed of a 3GHz processor. so obviously there are some tradeoffs relative to evertying-1GHz and 3GHz. this is much less apparent in the everything-2GHz since it's 2x as fast as everything-2GHz.