ive been looking through new egg for some computer parts and i saw that they had a intel quad core i5 and i7
i5 is about $200 and the i7 is about $290-300
its been on my mind that is it really worth paying about a hundred dollers more for the i7 or should i just take the i5?
advice would really help. thanks

Maybe these links will help.  There seems to be no easy answer although it seems that the i5 is your best bang for the buck if mounted on a proper motherboard with the proper chipset.

http://www.brighthub.com/computing/hardware/articles/48391.aspx

http://www.pcworld.com/article/171556/intels_new_core_i7_and_core_i5_processors_explained.html
 
http://www.tomshardware.com/forum/259526-28-feeling-ripped

basically it comes down to 2 things

If you answer yes to either of the following then you will want the i7

1. Do you plan to SLI vid cards? ( run dual video cards )
2. Do you do advanced things like HD video editing and 3D works? ( i7 has hyper threading while the i5 doesn't )

If you have said no to either of the above then the i5 is the route you should take; Save the money to put into a better graphics card. Although buying a video card now could have draw backs in the fact in march Nvidia is releasing there new card. ( HUGE price drops )

I've read the same comparisons.  I've been watching sales at Micro Center and if you're patient you can get some real steals.  This week they're offering the i7-920 for $199 and the i7-860 for $229.  Street price for the i5-750 is around $199.

The i7-9xx series have hyperthreading and use the LGA1366 socket and chipsets.  It's got full width PCI-E x16 lanes so it's best if you really want to go all out with SLI.  The motherboards are also expensive.

The i5-750 is the only quad-core i5 at the moment.  It does not have hyperthreading and uses the LGA1156 socket and chipsets.  If you do SLI you'll only have 2 PCI-E 8x lanes.  The motherboards are much less expensive than the LGA1366 boards.

If you can find one at a good price, the i7-860 sits somewhere in the middle.  It has hyperthreading and also uses the LGA1156 socket and chipset.  Again there's the limitation on SLI and the less expensive mobos.  It's also a 95W power part versus the i7-9xx at 130W.

I spend a lot of time reading up at www.tomshardware.com when planning a build.  There's also anandtech.com.  Most places I've seen recommend the i5-750 as the biggest bang for the buck.  Realize that when you get up over $200 for a CPU it's very small gains for very big bucks.  I haven't seen many sales on the i5-750, mostly sales on i7-920/860.  Guess the market has found it's price point.

As many have said, get a good CPU but don't put all your money there.  You'll often do better to skip the fastest CPU and put a little more in a better vid card and extra memory.  And never skimp on the power supply.  I've seen more builds destroyed by cheap power.

Also to add to this;

Never buy a crappy hard drive; you can have the best system in the world but if you hard drive is slow it becomes you bottleneck ^_^