Author Topic: New PC  (Read 6062 times)

Offline arnietheother

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Re: New PC
« Reply #18 on: Wednesday 12 July 06 20:12 BST (UK) »
Arquebus,
I fear my off-topic ramblings at the weekend may have added to your frustration, so by way of an apology, here's some of my more focused thoughts on choosing pc components.

"the potential supplier leaves it up to me to choose all the options....they are supposed to be the specialists.....how in God's name am I supposed to know what supports what?"
We all know it's because they don't know; all they have to go on is benchmark test results, which are not easily translated to efficiency in executing a particular graphics process. 
I think that the best way around this is to devise your own meaningful benchmark.  This might be the time taken to complete a processor-intense calculation on a particularly large file with a given number of applications open.  Time this on your existing system and set yourself a target (say 10 times faster) and think about how much you would pay for that performance increase.  See what the cost is of a machine capable of executing that task & try it out in the supplier's shop.  If they're any good, they'll let you install a program on their demo machine to try it out.  Something like a selective blur on a very large file would probably be a good example. 
I reckon that the people best placed to give an indication on machine specification to meet your benchmark would be the software developers.  You might get some indication from them of where to target your machine's performance. 

Here's some more of my thoughts on computers: -

On Hard discs, Ram and Paging:
I think a processor must be spending a lot if it's time paging on a small scale - swapping blocks of data between its cache ram and external ram, but because this happens very quickly & isn't evident, (as ram is about 1000 times faster than a hard disk) it isn't noticed.  So a large on-board ram cache should speed calculations quite a bit.  I suspect this is so for performing operations on graphics files. 
Paging ram to the hard disk is much more visible, and slower, due to the slow data transfer to and from a hard disk, and also because of the larger page sizes.  To minimise its effects, you could get a fast hard disc as this is the slowest component in the read/write process.  Choose one with very short access times (high spin speed).  Also, get one with on-board RAM, which will speed read/writes considerably (especially when beginning writes of relatively small files). 
It is possible with some OS's to select an area of the disk to be used as a swap partition, failing this, it may be possible to map the swap file to a particular area of the disk.  Not all bytes on a hard disk have equal access times. 
It might sound counter-intuitive, but it is possible to slow down the performance of some systems by adding RAM. (or put another way)  Some systems allow optimisation of paging by balancing the ratio of swap partition /swap file size to RAM size.  This can be unbalanced by increasing the RAM size.  In this case, you should install all the RAM and partition / install your OS afterwards. 
If you're using Photoshop under Windows to work with really large graphics files, see if you can limit the amount of memory it uses for things like 'undo memory' and 'tile cache size'.  I'm not a Photoshop user, but I know that this is possible in other graphics programs. 

And I'm not even finished yet...

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Offline arnietheother

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Re: New PC
« Reply #19 on: Wednesday 12 July 06 20:12 BST (UK) »
On RAID arrays:
"stripe means just one big disc, so there is is no point in having two"
This is not the whole story, properly configured, a RAID array could significantly reduce your paging times. 
Last time I looked at this, there seemed to be 4 or more standard arrangements of making a disk array, but when you think about it, there's only 2 basic principles:
1. duplicate the data on each disk - increase reliability & increase write / read times
2. distribute data over disks in order to increase write speed and reduce reliability by (at least) 50%. 
If you want to reduce paging times, you'd want to choose option 2. 

It's not necessary to have a hard disk on a pc - people have made systems with bootable flash drives.  Paging to flash is much faster than to a hard disk, but there's no room for file storage, so you need a USB hard disk for file storage.  The files are transferred to the flash area to be edited then copied back afterwards.  Flash memory does start to fail after a given number of write cycles (depends on type 1000 - 1000,000 write cycles).  Another tradeoff. 

"somewhere, is the best best best thing say, 100Ghz triple processors with 100G of Ram and 10G hard drives......."
That's in the right direction but at least one order of magnitude away.  Heavy duty calculations use clusters of computers & split the processing into chunks - each chunk being processed on a separate machine.  SETI are using screensaver time on many thousands of idle computers to detect non-random patterns in EM data.  Animation studios use render farms (clusters of networked computers) to perform ray tracing and image generation on each frame of a movie. Typically it can take one to several hours to render a single frame.  Dreamworks have recently upgraded their kit and are now using upwards of 500 clustered Linux machines to create (in effect) a several THz machine with a 500+ core processor.  It can render a single frame in 1/46 second.  Dreamworks have this kit because they're probably using something like cinepaint to render 32 or 64 bit-per-channel images.  I know it's not a feasible solution for a home / small business photo editor. 

On water cooling:
Thermal management of the average desktop PC is dire.  Fans are the most unreliable component in electronic / electrical systems (connectors win 2nd place).  If that's not bad enough, fans collect and distribute dust. 
There's an equation that describes how efficiently heat from a processor die gets to the surrounding air, it's just like ohms law:
heat flux = Temperature drop / thermal resistance
So, to get the maximum heat flow, you need to lower the thermal resistance. 
The thermal resistance is made up of:
* die to package (can't do anything about this)
* package to heatsink (use good quality thermal bonding medium )
* heatsink to air (use a heatsink with large surface area & approximately double its performance by using a fan). 
The weak link in this chain is the heatsink to air boundary, which, due to the large difference in thermal mass of metal and air is where most of the thermal gradient will be.  It gets much worse over time as the fans coat the heatsink with dust, and the heatsink-to-air thermal resistance increases, then your processor gets hotter. 
There are systems available with fanless processors, I've seen one that is thermally coupled to the case, which then acts as a very big heatsink.  This isn't a new idea, it's been done in car radios (and many other types of equipment) for decades.
Blowing the hot air out of the case through the PSU isn't such a bright idea anyway, there are components in the PSU whose deterioration rate is exponentially proportional to temperature, and these are filtering voltage spikes out of the supplies fed to the computer's components.  These age, the supply voltages get noisier & the components get hotter. 
You can use fans with integral air filters that blow into the case.  The case is then slightly pressurised with clean air, so the heatsink doesn't get contaminated with dust. 
Water cooling gives a very efficient heat transfer from the heatsink due to the much higher thermal mass of water, and will give more reliable cooling, as long as you're careful to avoid leaks.  It comes with the added benefit of silence. 

Right there's me off the soapbox - I knew it was a mistake to drop by the tech help board - I'm off back to photo restoration. 

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Offline Arquebus

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Re: New PC
« Reply #20 on: Monday 17 July 06 23:17 BST (UK) »
Thanks Arnie......I am somewhat further now....

Al.
ENFIELD...Colchester, DEARY & DIX...Norfolk & Oz, SLOLEY / SYMONS...Fremington Devon, BAKER...Deopham Norfolk, BANTACK...Ixworth, ALLISON...Suffolk / ALLISTON / ELLISTON/E...North East Essex, HOW /HOWE...North East Essex, SWALES..York / Middlesboro,METCALFE...York,  WOODS / MOLLETT / GREEN....Norwich, BRATTY...N.Ireland (Derry and Belfast), MORGAN...Bicknor / Coleford Glos. & Middlesboro. FENN / WENDEN / ROOKARD....North East Essex. SNOW...Hampstead & Devon. BULL...Colchester.

Offline Arquebus

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Re: New PC
« Reply #21 on: Wednesday 19 July 06 23:21 BST (UK) »
Just thought I would let those of you that are interested, I have gone the Socket AM2 route...You can imagine what that did to my wallet.

Al.
ENFIELD...Colchester, DEARY & DIX...Norfolk & Oz, SLOLEY / SYMONS...Fremington Devon, BAKER...Deopham Norfolk, BANTACK...Ixworth, ALLISON...Suffolk / ALLISTON / ELLISTON/E...North East Essex, HOW /HOWE...North East Essex, SWALES..York / Middlesboro,METCALFE...York,  WOODS / MOLLETT / GREEN....Norwich, BRATTY...N.Ireland (Derry and Belfast), MORGAN...Bicknor / Coleford Glos. & Middlesboro. FENN / WENDEN / ROOKARD....North East Essex. SNOW...Hampstead & Devon. BULL...Colchester.

Offline downside

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Re: New PC
« Reply #22 on: Thursday 20 July 06 02:11 BST (UK) »
What are you going to do with your old PC?

Leave it outside your front door - I'm sure someone will find some use for it.

downside
Sussex: Floate, West
Kent: Tuffee
Cheshire: Gradwell
Lancashire: Gradwell

UK Census information is Crown Copyright, from www.nationalarchives.gov.uk

Offline Arquebus

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Re: New PC
« Reply #23 on: Thursday 20 July 06 10:30 BST (UK) »
Upgrade it....amazingly it appears it can take 4G RAM!

It will get 2G, though.

It will then get used by Madame and as a backup for the data on the new one.

Al.
ENFIELD...Colchester, DEARY & DIX...Norfolk & Oz, SLOLEY / SYMONS...Fremington Devon, BAKER...Deopham Norfolk, BANTACK...Ixworth, ALLISON...Suffolk / ALLISTON / ELLISTON/E...North East Essex, HOW /HOWE...North East Essex, SWALES..York / Middlesboro,METCALFE...York,  WOODS / MOLLETT / GREEN....Norwich, BRATTY...N.Ireland (Derry and Belfast), MORGAN...Bicknor / Coleford Glos. & Middlesboro. FENN / WENDEN / ROOKARD....North East Essex. SNOW...Hampstead & Devon. BULL...Colchester.

Offline downside

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Re: New PC
« Reply #24 on: Friday 21 July 06 14:18 BST (UK) »
Ahhhhhhh a happy ending  :)

downside (not envious as he has upgraded to a Pentium III with 256MB RAM)
Sussex: Floate, West
Kent: Tuffee
Cheshire: Gradwell
Lancashire: Gradwell

UK Census information is Crown Copyright, from www.nationalarchives.gov.uk

Offline Arquebus

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Re: New PC
« Reply #25 on: Friday 21 July 06 20:22 BST (UK) »
God, if that's upgrading, what the hell was it like before?

It must have been so slow your email came by horse and cart.

Al.
ENFIELD...Colchester, DEARY & DIX...Norfolk & Oz, SLOLEY / SYMONS...Fremington Devon, BAKER...Deopham Norfolk, BANTACK...Ixworth, ALLISON...Suffolk / ALLISTON / ELLISTON/E...North East Essex, HOW /HOWE...North East Essex, SWALES..York / Middlesboro,METCALFE...York,  WOODS / MOLLETT / GREEN....Norwich, BRATTY...N.Ireland (Derry and Belfast), MORGAN...Bicknor / Coleford Glos. & Middlesboro. FENN / WENDEN / ROOKARD....North East Essex. SNOW...Hampstead & Devon. BULL...Colchester.

Offline downside

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Re: New PC
« Reply #26 on: Saturday 22 July 06 00:11 BST (UK) »
Hi Arquebus

What have processor speed and memory got to do with sending and receiving email?

They can't arrive any faster than ones internet connection permits which in my case is broadband.  Am I to conclude that I'll be able to type an email faster on your latest computer?  :)

As you can probably tell I'm not a power user - but I get by.  I've just done a Windows Vista test and they reckon my current PC is not up to the job of running Windows next release.  I hope that support for Windows XP continues for a few more years.  Microsoft have recently stopped supporting Windows 98 so I reckon I should be able to carry on with my current system for at least 6 years.

downside
Sussex: Floate, West
Kent: Tuffee
Cheshire: Gradwell
Lancashire: Gradwell

UK Census information is Crown Copyright, from www.nationalarchives.gov.uk