Greatest way to start a flamewar ask about Intel vs AMD.
AMD makes a good chip (I have one of each) but Intels chips are the equil up until you get to the best Intel chip where the price goes out the window.
Once upon a time AMD made a faster (clock for clock) processor than the Intel. AMD decided to get away from processor clock speed and changed to a reference number based upon the speed of Intel processors.
Intel did not stand still and added two features hyperthreading and faster FSB clock speeds. So now an AMD is a little optimistic on their clock speeds
. The Intel PIV (3.0GHz/800FSB) will perform better than the 3200+ AMD Athlon XP. So once you get off of the lastest and greatest the price is a lot closer than you think (Less than $60). Hyperthreading is used by Photoshop so you are getting a boost that the AMD will not give you. A lot of the cheaper systems are taking shortcuts with the chipset/memory to get a lower cost system. An AMD can be a great buy but make sure the other stuff in the computer is of a good quality.
(IMHO) The AMD 64 is interesting but should probably be avoided since it is ahead of the curve. No OS support and no Photoshop support in 2 years everything will catch up but why run slower now so that right before you replace your computer it will get a little faster.
You should always try to work in 300 dpi… anything more is a waste of memory unless your creating a billboard for the freeway…
300dpi is meaningless (it's an old typesetter term that does not really apply to modern computers) the main thing is what are you editing at what resolution. (And BTW freeway billboards are more like 25dpi with some having pixels the size of your thumb).
Look at your picture source information (camera, scanner, whatever) multiply it by 3 (standard digital camera) or 6 (Raw mode or high end scanner). Then multiply it by 6 for layers (they are like peanuts once you start you just keep going with them). Now take that answer and throw it away just budget for 1 GB min of RAM you will thank me later.
Get as big a monitor as you can, with a limited budget look at the old glass monitors they are actually cheaper and better for photoediting than the flat panels.
Hard drives are also cheap 200GB are now go on sale for $100 (USD). So go big.
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Things to watch for:
If it is a bundled system make sure you are getting a real chip AMD vs Intel and not a lower FSB version of the chip. Make sure the RAM on the motherboard is as fast as possible (PC3200 at least) and that you can expand it to 1GB without having to throw away the other chips. Get a big hard disk (speed has pretty much caught up so all are generally equil), but budget for a second drive ASAP.
If at all possible keep away from on the motherboard video. This tends to share the on board memory and slows down the overall performance of the computer.