Yeah some theory about last 2 numbers but that was related to QX9650s IIRC.
Let us know how your Q820A405 does...
now here's the 5 babies lined up
Intel Core 2 Duo E8600
Q820A599 07/15/2008
SLB9L MALAY
2V82316
**0376
**0464
**0537
**4506
**5146
results so far