Dropping Packets Randomly

I have a SuperMicro Server based on the X9DR3-LN4F+ motherboard from SuperMicro. Original intentions for the system were quite different from what it has ended up serving, but that happens.

It is being used for a IP Video Security DVR/Monitor.
Operating System is Windows 7 64bit (its appropriate for the recording software)
The cameras are Axis P1354 and P1354-e (difference being an internal vs external enclosure).
The switch is an SG300-10MP

Obviously the original setup was a bit different, but I am trying to eliminate every possibility here – so for now I've got the server and cameras on the same switch in the same building.

The nics onboard the motherboard are Intel I350 (x4) – the drivers are the newest available from Intel's site.

Upon a fresh boot, the streams (in MJPEG or MPEG) are fine – 30fps, no apparent dropping of packets. After a random period of time I start to see the feeds become ragged, frame rate drops.

If I do a ping to the switch from the server – I also see random packets drop – sometimes 1 or 2 – sometimes 5,6,7 – no apparent pattern to this behavior. If I do a ping to a video device I also see random packets drop. If I add to this another device, say the router, I also see packets drop. The thing is – they don't even drop at the same time. So its not some sort of critical failure somewhere – while one ping may be dropping packet after packet, the other two are happily pinging away (sometimes).

I have swapped out the switch. Firmware is at its newest, and besides, when viewing the cameras from my laptop (from the same switch), I see no evidence of this happening, leading me to believe the switch is not the culprit. The switch as of now is basically acting as an unconfigured Layer 2 switch – but was in a layer 3 mode with vlans for voice and video (voice prioritized over the camera streams). Its basically become an isolated desktop test bench setup now. To the point I've disconnected and isolated the switch, cameras, and servers from any other equipment.

I've actually gone through nic settings and switch settings, ensuring that any green settings are off, tried different nics (of the 4 onboard) on the server – teamed nics on the server and switch. I even went so far as to reload Windows 7 (I'm less of a Windows guy, and a bit more Linux/Unix)

I've upgraded the motherboard BIOS to the latest revision.

I've looked for any particular trouble with these NICs, but found nothing that stood out – basically recommendations to turn off green settings and whatnot.

Additionally, I've see this behavior repeat itself identically in an entirely different setup. I was using a Cisco WET200 bridge (I am in a remote location and the only test bench area I had was without any sort of ethernet wiring) on a different switch, in a different building – connected over fiber to the switch the cameras are on.

Does anyone have any recommendations at this point? I've never had this much trouble with a simple setup like this, and its very frustrating. I haven't pulled a dump of a switch port to see what is happening with the packets, but if it seems worth a go I can reconfigure the switch to mirror a port and throw a Wireshark on it, at least see for certain whether the ping packet is dropped before the switch or on the way back from the switch, I suppose.

Next try is to purchase a PCI-e NIC to try (I hate being out of the office – I would have one I could grab and try) – but wanted to put a quick question out to see what else I can try or look for.

Thanks in advance!