I'd buy the AMD Athlon II X4 630 system - the quad core Athlon II will be far better than the dual core Intel Core 2 Duo E8500 for multitasking - your main concern. The Athlon II does overclock a bit, but not very well compared to the Core 2 Duo 45nm CPUs (E7000 and E8000 series).
The Intel Core i3 is slower than the Athlon II X4 630 on most multi-threaded benchmarks, however, the i3 is faster than the Athlon II in gaming. Considering you're multitasking more than gaming, the Athlon II X4 is a better choice. However, if power consumption is a major factor as to whether you'd get the CPU or not, the Athlon II X4 630 consumes a lot more power than the Core i3 530.
Define what you consider multitasking please. Also what you will use the system for. The AMD system seems to be overpriced(I am thinking just the tower though).
Multiasking and programs that will actually use 4 cores are different things. Being that say you multitask alot but yet you're just now sick of the p4 system I am doubting you need more then a new modern dual core chip.
Why would the AMD 630 cost $500? Does it include the motherboard and other stuff? The same question does apply to the Intel processor as well. (Seems $300 is too expensive for the E8500.
Anyway if you prefer the superior performance NOW for most PC games. I'd get the E8500. It is just because of the superior overclocking potential.
However, the AthlonX4 630 does come close in overclocking potential as well, not to mention there is still a possible upgrade path on that Athlon if you have a new motherboard like the 790G motherboards.
What I mean by multitasking: numerous program open such as Web browser x4 + Outlook + Photo's + website design program (occasional Adobe Photoshop with that for image creation).
I don't play games on my PC - that is why I have an xbox 360 (sorry to those hardcore PC gamers)
Taking the advice of past posts I had a look at the home build section and came up with this:
I'm in Australia so price in $AUD - I priced this at $465 (me build) OR + $75 (=$540) if I get them to build it.
* CPU: AMD Athlon II X4 630 2.8GHz Socket AM3 95W
* MOBO: ASUS M4A785T-M AM3/AM2+/AM2 AMD 785G HDMI Micro ATX AMD Motherboard
* RAM: DDR3 PC 12800/1600 (2x1gb) Corsair XMS3 - dual channel setup - (this RAM is alitte more high spec to cope with overclocking - would this be accurate??)
* HSF: None Required
* HDD: Seagate Barracuda 7200.12 ST3500418AS 500GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
* PSU: what ever comes with the case = will be 420w
* GPU: None Required - This system will use on the onboard video, since graphic power is not a priority.
* DVD: Lite-on Super AllWrite SATA - 24x OEM
* Case: COOLER MASTER Elite 341 MicroATX Mini Tower Computer Case
For a similar setup as above with
* i3 530 (to be overclocked)
* MOBO: Gigabyte GA-H55-UD3H
This would cost me $520 for all parts + $75 for build (unless I learn hwo to do it) = $595
Yep, in this budget get that mATX mobo, X4 630, Team Elite DDR3 4GB PC-12800/1600 (2x2GB) CL9 1.65V Ram, LG GH22NS50 SATA DVD Re-Writer (22x - Black), Seagate Barracuda 500GB 7200RPM 16MB SATA 3Gbs, Cooler Master Elite 331 - Black/Silver ATX Tower Case (420W) for a total of 558.8.
You can consider the AMD Athlon II X3 Triple Core 435 2.9GHz, it's very good for the money and an ATX mobo, GA-MA785GT-UD3H.