What if computers could do this or that?

[nanowatt]

Ok so this is more of a "science fiction" discution but is just for my own curiosity.PLEASE feel free to put questions related to this topic i am sure someone will answer.

Last nigt before i got to bed some questions came up and here i am asking you.

1.What would take for a graphical card to be able to use motherboard ram beside having same frequency  and bandwidth?

2.Preset motherboards use cooper circuits with ajusted length in order to make them precise and to communicate with other components even more a circuit have to be an exact length for different operations in order to be precise.Why we can't use fiber optics circuits for motherboards?Is the same thing right?A circuit use electrical impuses,fiber optic use light but doest that light have to be processed?

I have a few more questions but i want to see if someone is interested so i don't talk alone.

3.I am wondering could we use a motherboards's expantion(pci all lenght) for upgrades?For example a pci card with lets say 8gb or ddr3 memory as a upgrade or a processor.What would take to be able to do such thing with an expantion slot?Drivers?A precessiong unit for each card to give it a "purpose" (where and for what to be used)?

[RelentlessAF]

To answer number one the GPU uses GDDR RAM since it's better for transferring graphical data than DDR3. There wouldn't be a real purpose to using the RAM in your Mobo.

[Tea1337]

In copper, electricity travels at the speed of light, just like fiber optics. And for the first one GPU's would become bulky and it wouldn't FAST enough for the GPU to be able to use like laptop ram on it.

[Zeke]

I think GPUs integrated into CPUs do "borrow" some of your RAM.

[Cubit481]

 

2.Preset motherboards use cooper circuits with ajusted length in order to make them precise and to communicate with other components even more a circuit have to be an exact length for different operations in order to be precise.Why we can't use fiber optics circuits for motherboards?Is the same thing right?A circuit use electrical impuses,fiber optic use light but doest that light have to be processed?

I have a few more questions but i want to see if someone is interested so i don't talk alone.

i dont think for such short distances fibre optics will work that well compared to copper...and also the circuits will become much more bulky...

[Altecice]

RAM is very slow to access on CPU terms (not as slow as the hard drive) but still slow. As for every memory read/write the GPU needs to do to the RAM, the CPU will have to be stopped then it will have to run its ISR (Interrupt Service Routine).

 

The thing with PCI-E slots is they are basicically IRQ lines, old computers used to only have a few of these but now we have PCIE connections with 100's. What the IRQ lines do is they don't talk to the processor directly they talk to a controller called the DMAC. Direct Memory Access means that the DMAC can access memory without having to interrupt the CPU (thus slowing everything down) they can do it "for" the CPU and keeping memory to memory transfers fast. So in theory yes the GPU does talk to RAM already but its already been "sorted out".

 

Also with your fiber optic idea. The issue with this is the signal will have to be encoded into light > travel > be decoded back into voltages at the end. So adding delay.

[nanowatt]

In copper, electricity travels at the speed of light, just like fiber optics. And for the first one GPU's would become bulky and it wouldn't FAST enough for the GPU to be able to use like laptop ram on it.

If what you say is true then why servers use optic fibre to transfer data and not usual cables?

[nanowatt]

To answer number one the GPU uses GDDR RAM since it's better for transferring graphical data than DDR3. There wouldn't be a real purpose to using the RAM in your Mobo.

That makes sens but i am wondering something.We were stuck with ddr3 for a long time now ddr4 is about to come out yet is not as fast as gddr5.What makes a gpu be able to use such a high speed memory that a cpu doesn't have and why it took to long for cpu momemory to make a new step?

[Tea1337]

If what you say is true then why servers use optic fibre to transfer data and not usual cables?

There is less resistance so they don't have to use as much power, it's also lighter and more easy to work with in come cases.

[ForsakenLive]

we already have this technology, optical processors are currently used on the highest tier of military weapons such as aircrafts., however it's extremely expensive and not available to the public.

Copper can make runs up to  30cm (approximate) on very high frequency data transfers, hence the size of an ATX motherboard.

[ForsakenLive]

That makes sens but i am wondering something.We were stuck with ddr3 for a long time now ddr4 is about to come out yet is not as fast as gddr5.What makes a gpu be able to use such a high speed memory that a cpu doesn't have and why it took to long for cpu momemory to make a new step?

There isn't much use to a DDR5 processor, it's not a physical limit, CPUs cannot be fed at such high speeds, going over DDR4 at this moment in technology for a CPU is pointless, unless you are using some sort of Stackable RAM Co-Processor, like the Xeons that started to come up.

[RelentlessAF]

That makes sens but i am wondering something.We were stuck with ddr3 for a long time now ddr4 is about to come out yet is not as fast as gddr5.What makes a gpu be able to use such a high speed memory that a cpu doesn't have and why it took to long for cpu momemory to make a new step?

GDDR RAM is good at transferring Graphical data but not regular general usage data like DDR3. DDR RAM is more well rounded and is why the CPU uses it and GDDR is single purposed for video data making it more effective for a GPU and a complete waste for a CPU.

[Altecice]

GDDR RAM is good at transferring Graphical data but not regular general usage data like DDR3. DDR RAM is more well rounded and is why the CPU uses it and GDDR is single purposed for video data making it more effective for a GPU and a complete waste for a CPU.

 

Also dont forget the DDR ram requires a delay to make the sections of memory about to be read or written to ready. Vs GDDR that does not require this pause.

 

Also if i remember correctly GDDR can be written and read to simultaneously. (although this is not used much in modern GPU's)

[Cubit481]

Also dont forget the DDR ram requires a delay to make the sections of memory about to be read or written to ready. Vs GDDR that does not require this pause.

 

Also if i remember correctly GDDR can be written and read to simultaneously. (although this is not used much in modern GPU's)

seconded... ..ddr is only capable to reach a bandwidth like 30-50 GBps whereas gddr can go all the way to 200-300 GBps...

[schwat]

If what you say is true then why servers use optic fibre to transfer data and not usual cables?

 

I believe this is for several reasons.

 

1) You can pack way more fibers into a single cable than you can pack copper wires. Fiber is extremely thin & only needs a very thin sheath because it is not carrying voltage. Copper needs to be a certain gauge because resistance of a wire is a function of length * diameter. The thinner the wire the higher the resistance & thus shorter distance you can run a signal.

 

Also you can even carry multiple signals along a single fiber if you're using multimode fiber. 

 

2) Transmission distance. You can send a higher bandwidth signal farther over fiber than you can with copper. For example you can send 10Gbps over copper but only about 50 feet. You can do this over kilometers for fiber.

 

3) Transmission distance pt 2. You need fewer signal repeaters with fiber than you do with copper. Every long distance transmission line will have repeater stations that boost the signal after a given distance. I can't remember the exact difference off the top of my head.  

 

4) Interference. When running a bunch of signals along copper wire you have to be careful to minimize crosstalk between conductors especially when running over long distances. This usually involves using shielded twisted pair wire which means even MORE bulk than a single piece of fiber. Fiber is not susceptible to EMI interference.

 

I actually was a fiber technician for a couple years doing infrastructure installation. Like big 300+ mile jobs running large cables for communication backbones, not like wiring up a datacenter or anything.