Need advice, constant BSoD

Since I put my PC together back in October, I've been having these crashes, though not always BSoD. Some times they are non existent, and then return with a vegence. Everytime I boot my computer from being powered down for 5 min or longer, my pc doesnt recognise my video multimedia device and pci device. If I scan hardware in device manager it removes the unknown icons and shows everything normal. I also blue screen fairly often with messeges like the one I posted below. this has been happening for as long as I've had this pc.

Here are my computer specs: ABIT FATAL1TY AN8 Socket 939 NVIDIA nForce4 Ultra ATX AMD Motherboard , EVGA Geforce 7800GTX KO 256MB 256-bit GDDR3 PCI Express x16 Video Card, AMD Athlon 64 X2 3800+ Manchester 1GHz HT 2 x 512KB L2 Cache Socket 939 Dual Core Processor, Creative Sound Blaster X-Fi XtremeMusic 7.1 Channels 24-bit 96KHz PCI Interface Sound Card, NEC DVD Burner Black IDE/ATAPI Model ND-3540A, CORSAIR XMS 512MB 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200) System Memory x4, Antec NEOPOWER 480 ATX12V v2.0 480W Power Supply, Seagate Barracuda 7200.8 ST3250823AS 250GB 7200 RPM Serial ATA150 Hard Drive, Lian Li V SERIES PC-V2100B Black Aluminum ATX Full Tower Computer Case, Logitech Z-5500 505 Watts 5.1 Speaker, Saitek Eclipse keyboard, Logitech MX1000 mouse, Razor Copperhead mouse, Ergodex DX-1 keyboard, Logitech Premium USB Headset 350, and NEC Multisync LCD1970gx monitor.

My internet connection is a 8m dl comcast cable connection.


Heres the windows analysis,

BCCode : 9c BCP1 : 00000004 BCP2 : 8054D5F0 BCP3 : B2000000
BCP4 : 00070F0F OSVer : 5_1_2600 SP : 2_0 Product : 256_1


Hardware failure: replace failed component

Thank you for submitting an error report.

Problem description

The error was caused by an unrecoverable hardware error which forced the operating system to stop functioning.

Although we know the problem is caused by a hardware component, unfortunately the error report does not contain enough information to tell us the specific component. More than likely the problem is being caused by problems with one or more of the following computer components:

Random Access Memory (RAM)
System board
Central Processing Unit (CPU)
Power supply
Recommendations

If you have received this error more than once, it could indicate a serious problem with your computer. We recommend that you do the following:

Back up your files to avoid data loss in case of a complete hardware failures.
Contact the original manufacturer of your computer or your local computer repair shop. Either will have advanced hardware diagnostics to determine the specific component which is failing.


The following files will be included in the error report: COCUME~1EvertLOCALS~1TempWERa796.dir00Mini041206-02.dmp
COCUME~1EvertLOCALS~1TempWERa796.dir00sysdata.xml