What motherboard are you using? You might be having a problem with the motherboard chip set (nForce2/3 maybe??) and the ATI card. Not only are you moving up in power requirements, but also moving between makes of cards. I've heard that nforce2/3 with ATI cards have issues.
I still have...
This is the new pci-e version. Found it on Dell's website as a replacement part for the XPS models.
http://accessories.dell.com/sna/productdetail.aspx?c=us&l=en&s=dhs&cs=19&sku=DN804&mfgpid=167776&chassisid=8242
You can also get 10% off if you pay through PayPal...
I just checked my order at TigerDirect. The status changed from Backorder to In Process. Things are moving now.
This is correct. There are s939 89 watt and 110 watt versions of the 4400+ X2. There are also slower chips that come in 89 watt versions. I would go for the 89 watt versions...