Cpu upgrade, old system

Hello, I'm trying to breath a little life in an old system. When I put this amd athlon 64 x2 6000 (ada60001aa6cz) into the below system it locks up at the "dell" startup screen. But after a couple of hard shut downs, it somtimes starts, but then works perfect 50% of the time. Any ideas of what i can do to keep it stable? Computer Type ACPI Uniprocessor PC Operating System Microsoft Windows XP Home Edition OS Service Pack [ TRIAL VERSION ] Internet Explorer 8.0.6001.18702 (IE 8.0) DirectX 4.09.00.0904 (DirectX 9.0c) Computer Name DESKTOP Date / Time 2012-05-13 / 10:28 Motherboard: CPU Type AMD Athlon 64, 2000 MHz (10 x 200) 3200 Motherboard Name Dell Dimension E521 (2 PCI, 1 PCI-E x1, 1 PCI-E x16, 4 DDR2 DIMM, Audio, Video, LAN) Motherboard Chipset nVIDIA GeForce 6150, AMD Hammer System Memory TRIAL VERSION ] DIMM1: PNY Electronics 1 GB DDR2-800 DDR2 SDRAM (6-6-6-18 @ 400 MHz) (5-5-5-15 @ 333 MHz) (4-4-4-12 @ 266 MHz) DIMM2: PNY Electronics [ TRIAL VERSION ] DIMM3: PNY Electronics [ TRIAL VERSION ] DIMM4: PNY Electronics [ TRIAL VERSION ] BIOS Type ward (08/02/07) Display: Video Adapter NVIDIA GeForce 8800 GT (512 MB) 3D Accelerator nVIDIA GeForce 8800 GT Monitor Aoc 2436 [24" LCD] (AJMBAHA128927) Multimedia: Audio Adapter C-Media CMI8738/C3DX Audio Device Audio Adapter SigmaTel STAC9227X @ nVIDIA nForce 430 (MCP51) - High Definition Audio Controller Storage: IDE Controller NVIDIA nForce 430/410 Serial ATA Controller IDE Controller NVIDIA nForce 430/410 Serial ATA Controller Disk Drive WDC WD2000JS-00MHB0 (200 GB, 7200 RPM, SATA-II) Optical Drive LITE-ON DVDRW LH-20A1S (DVD R9:8x, DVD-R9:8x, DVD RW:20x/8x, DVD-RW:20x/6x, DVD-RAM:12x, DVD-ROM:16x, CD:48x/32x/48x DVD RW/DVD-RW/DVD-RAM) SMART Hard Disks Status OK Network Adapter Broadcom 440x 10/100 Integrated Controller (192. [ TRIAL VERSION ]) Motherboard Properties Motherboard ID 08/02/2007-C51MCP51-6A61HM39C-00 Motherboard Name Dell Dimension E521 Front Side Bus Properties Bus Type AMD Hammer Real Clock 200 MHz Effective Clock 200 MHz HyperTransport Clock [ TRIAL VERSION ] Memory Bus Properties Bus Type Dual DDR2 SDRAM Bus Width 128