So I finally caved in and got some new hardware. It was fortunate that I found cheaper options for the NetGear FVS336G and the only place for Seagate Barracuda 1.5 TB drives at NewEgg. Figured with the shipping I may as well let it ride.
Following the basic memory and chip upgrade instructions the only difference would be the use of an AMD LE-1660 (Lima) 2.7 GHz.
G.Skill 2GB DDR2 667Mhz PC-5300 which was on sale for $30 that week.
First things first, remove the installed drives and label them so you know which order to put them back. WHS uses DE and you don't want to confuse the operating system and inadvertently trashing your data. The main bay is locked and I used a quarter to twist this clockwise (a large screwdriver would work but beware the groove marks if its tight).
Slide the gray top cover forward gently and it should slide out from the grooves. There are four actions items from this angel that you need to do.
Make sure to mark where the cables match up and be careful not to switch things around later (it could be bad).
Gently remove the black cable as well and gently move it out of the way.
Twist the blue tabs outward to unlock the backplane. Its this backplane that serves to connect the SATA disks.
Put your hand in and reach for the spaces with your fingers, then gently pull up. Be careful as there's a (barely used) thermostat you don't want to damage as you do this.
Remove the two-(2) small black screws on the front lower right side of the casing.
There's an insulated cable in there thats pressed against it and will usually cause it to pop out (don't loose the screws!). Do this gently (I keep saying that) since too much pressure on these small screws could ruin their tread -- mine's almost that way.
Use a medium sized Philip's screwdriver to remove the two-(2) anchoring screws between the casing and power supply.
Gently pull this tray out while gently pushing left as the components tend to snag.
Welcome to the guts/brains of your HP EX475 system.
Disconnect the power supply cable from the board and move it out of the way.
Remove the stick of memory as well. You'll need all the space to remove the heatsink from the chip by unscrewing it in an X-pattern so as to relieve the pressure on the chip gradually.
Then with a twisting left and right action gently remove.
With pure alcohol (pick one type as long as its more than 70% proof such as vodka or isoprophyl) make sure to clean the heatsink and set it aside to dry.
For those who've never replaced a chip before, there's a lever that needs to be lifted before you can remove the chip for replacement. Be careful to re-orient the new chip's pins the same way (don't forget to wipe the beads of sweat off your brow as any of it dripping onto the board isn't good ... and close your mouth).
A little goes a long way in terms of the heat seal, just a 1.5 grain of rice will do.
Then put Humpty-Dumpty together again and reverse the steps above.
Since I was using pure isopropyl and drinking that could cause major gastric distress (check the label), best I could do was step outside for a beer and a smoke. :-)