Yes, and I think the "E9" tells you how many chips are on the DIMM (this class of motherboard needs DIMMs with x8 chips, for some reason,
No, in this case E9 refers to ECC, and CL9 latency. Kingston's part numbers are hard to read, but I have had some practice!
http://www.valueram.com/datasheets/KVR1333D3E9SK2_4G.pdf
KVR1333D3E9SK2/4G = Kingston value RAM, 1333MHz, DDR3, ECC, CL9 latency, thermal Sensor, kit of 2, total 4GB of RAM (2 x 2GB)
Note that there is no "R" in the latter part of the SKU, which indicates that it is unregistered memory (aka, unbuffered). In contrast, this is registered memory:
KVR1333D3D8R9SK2/4G = Kingston value RAM, 1333MHz, DDR3, Dual Rank 8 bits per chip, Registered, CL9 latency, thermal Sensor, kit of 2, total 4GB of RAM (2 x 2GB)
http://www.valueram.com/datasheets/KVR1333D3D8R9SK2_4G.pdf
For some reason, Kingston leaves out the rank and bits per chip on the unregistered memory. They also leave out any E for ECC on registered memory, but it seems all their registered memory is also ECC.
If you click on the "Note: Supports 1-Gb and 2-Gb x8 devices only - Intel 3420 / 3400 Chipset Memory Requirements" link from this page for the Supermicro X8SIL-F:
http://www.supermicro.com/xeon_3400/Motherboard/X8SIL.cfm
and look at Table 1, you see that the motherboard will work with single- or dual-rank unregistered memory with 8 bits per chip (x8). But your maximum capacity is higher with dual-rank. That is because of a limitation of the memory controller used with this chipset.
Unfortunately, the unregistered memory Kingston SKUs do not specify whether it is single- or dual-rank. The registered memory SKUs do: S, D, Q for single-, dual-, or quad-rank. Note that unregistered memory only comes in single- and dual-rank (i.e., quad-rank will always be registered). But you can figure out whether the unregistered memory is single- or dual-rank by looking at the datasheet:
http://www.valueram.com/datasheets/KVR1333D3E9SK2_4G.pdf
ValueRAM's KVR1333D3E9SK2/4G is a kit of two 256M x 72-bit 2GB (2048MB) DDR3-1333 CL9 SDRAM (Synchronous DRAM) ECC memory modules, based on eighteen 128M x 8-bit DDR3-1333 FBGA components.
Eighteen chips x 8 bits per chip = 144 bit width. Now, a single ECC rank is 72-bits wide (non-ECC ranks are 64 bits wide), so 144 bits / 72-bits = 2 = dual-rank.