Want your advice

I'm new-ish to building PC's and this will be my first complete build. Just looking for feed-back here. Any opinions/advice/tips on other items to get or swap out would be great. Are these parts compatible? Will I be spending days trying to get these parts to work well together?

Have already purchased:

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CPU: Intel Core2 Quad Q9400 2.66GHz 6MB L2 Cache LGA775 95W Quad-Core Processor
@ Microcenter for 179.99
It was 229.99 @ Newegg


Case: Antec Nine Hundred Black Steel ATX Mid TowerComputer Case
@ Microcenter for 87.99 109.99 @ Newegg

With: 2 more 120mm Antec case fans

CD Drive: Samsung DVD burner for 24.99

Monitor: Acer 20 inch wide screen LCD (have a CRT right now)
@ Microcenter for 139.99

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Microcenter is having a big sale until 2/28 and its down the street from me.


Will get:

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Motherboard: GIGABYTE GA-EP45T-UD3P LGA 775 Intel P45ATX Intel Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

GPU: EVGA 512-P3-N879-AR GeForce 9800 GTX+ 512MB256-bit GDDR3 PCI Express 2.0 x16
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

PSU: CORSAIR CMPSU-650TX 650W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

RAM: WINTEC AMPX 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR31333
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

HardDrive: Seagate Barracuda 7200.10 ST3250410AS 250GB7200 RPM 16MB Cache SATA 3.0Gb
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

CPU Fan: ZALMAN 9500A 92mm 2 Ball CPU Cooler
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

With: Arctic Silver 5 Thermal Compound

Speaker: Creative Inspire T3100 2.1 2-way Speakers
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Key/Mouse: Microsoft QQA-00001S Black USB Digital

Thank you for your time and advice.