Microsoft upgrade advisor tool says that my XPS420 meets the hardware requirements for WIN7. Dell list does not show the XPS420 as being WIN7 compatible. Who is correct? Thank you.
As far as Dell are concerned the XPS-420 is an obsolete machine, so you shouldn't expect any updates on anything from them. My XPS-420 has been running Win 7 64 bit with 3GB of memory for 6 months now with infinitely better reliability and performance than the 32 bit Vista it came with. Upgrade it as fast as you can after checking for drivers for any additional hardware you may have.
XPS 420, 8GB, Windows 7 Home Premium SP1 64 bit
The XPS 420 is compatible with Windows 7 (I have installed it without issue). If you go to the Dell support page for XPS 420 drivers it does not show Windows 7 since Dell never shipped the XPS 420 with Windows 7 (but that doesn't mean that it's not compatible).
Just make sure you are running the A07 bios before you upgrade, which will be the last bios update for this model. Win 7 runs great on mine. I've run both 32bit and 64bit and both are fine.
Why is the A 07 bios necessary before upgrading the 420 to Windows 7 64 bit???
My hard drive recently died (Vista Ultimate) and have a new hard drive coming in a day or so along with am upgrade version of Win 7 Pro 64 bit.
Since I'll be installing a new WD 1 TB SATA II drive before clean installing Win 7 Pro, how do I upgrade the bios on a non functioning, non bootable computer prior to adding the Single new hard drive?
XPS 420, Intel Core2 Quad 9650, Two Vertex 2 180GB SSD's in Raid 0, Two 1 TB WD Cavier Black 7200 RPM 64 MB Cache SATA III Drives, 8 GB DDR2 SDRAM PC2 6400 at 800MHz, Seasonic X Series 660 Watt PS, XFX Radeon HD 6990 GPU, Windows 7 Pro 64 bit
Optiplex 990 MiniTower, i7 2600, Seasonic 650 Watt X Class Gold Power Supply, Win 7 64 bit Pro on Two OCZ Vertex 3 MAX IOPS SSDs in Raid 0 array on SATA 3 Intel headers, 1 TB WD Cavier Black 64 MB Cache SATA III, 16 GB DDR3 Crucial RAM, soon to replace stock video card, NEC USB 3.0
Short answer you dont.
Other answer would be to make a bootable USB flash drive with dos and download the bios update file.
Make dos bootable cdrom with bios file
install vista on the drive, download bios, install.
VISTA DRIVERS work with windows 7 just as win2000 drivers work with XP.