Update - Successful Shuttle K-45 implementation with 4gig of ram
I don't know if anyone saw this thread, I did go out and pick up the Shuttle K-45 mentioned above with (overspec) 2x2gig sticks of generic DDR2-800 with a legacy PCI 3Com 3c905c NIC and a single 1tb WD Green drive - powered by a Core2 Duo E7300 (2x3mb cache, 45nm). The whole rig is running in this tiny case which is smaller than a shoebox, the only additional element I added was an extra Antec tri-cool 92mm fan which has the power switch set to the lowest speed. I used the 3c905c based on the advice above, it is clear that currently the onboard gb nic isn't supported (which is indeed a shame).
My objective was to build a small, low power consuming ESXi box that I could leave on 24/7 and not generate too much heat and also to reduce my astronomical domestic power bills to some extent; the noise generated by the little K-45 is higher than you'd expect but it seems to work ok.
I performed diagnostics on the ram with Memtest86 overnight prior to the build, the memory's only running at 667 speed but that seems to be fine - I'm finding so far that it's a pretty good solution. I overcame the lack of optical drive support by building the system initially with its lid off and a free-floating PATA CDRW drive reading the ISO file, I was able to externalize this arrangement by booting the system to an external 5.25" HDD caddy (open) with the CDRW drive plugged in there - it seemed to work perfectly well, it allowed me to install the ESXi system onto the 1tb drive without any significant issue.
I have built a series of VM's on there and performance is good, I certainly wouldn't want to run this thing on anything less than 4gig of ram though - one concern I have currently is that I have noticed that SMB data transfer from one of the VM's (WinXP-Pro SP3) is below par; it's transferring across large binary files to other workstations at about an average of 5.7m/sec which is compared to stand-alone machines on the same network (similar source drive) which can meter out data at 8-9m/sec and peaking at nearly 10. I'm not entirely sure why this is, I can't see any overload of ESXi when I look a the performance graphs; the HDD itself is more than capable of shuffling data out, I've been able to do this on an earlier experimental build so I'm currently thinking the problem is more with my ESXi config (I'm relatively new at this).
Overall though I'd say that this is a pretty good solution for a low power, small black-box solution that is ideal for domestic situations - the lack of an optical drive so far has only been a minor inconvenience during installation, the rest of the time it just sits there and does its job.
