Lowest cpu for multiple plex transcodes

I am getting ready to build a dedicated server to house disks and run plex plus backups on my network rather than running it on my main system. I want to build a smaller system that is a little better in power efficiency and such. So my question would be has anyone tested several simultaneous transcodes on a smaller CPU like an i3 or i5 or even one of the AMD APU units like an A10? I was hoping I could get by with like an i3 with a hundred dollar motherboard, but I'm wondering if that could support, say 4 or 5 simultaneous transcodes at one time. Any thoughts?

With 4-5 transcodes.. depending on the original source (720p/1080P/etc.), I wouldn't recommend anything lower than an i5. I ran Plex on an HP elitedesk 8200 with an i5 and could transcode videos for 3 devices... didn't try more though since most of my stuff is already in MP4 or MKV format that direct-streamed to my Roku and the kids Samsung tablets. 3 transcodes pretty much pegged the CPU... but they were all 1080i recorded TV content.

So maybe my best bet would be to just upgrade my rig and leave the current system as is? I mean, nothing wrong with too much horsepower I guess.

Current rig would be great. I myself am getting on the plex bandwagon. Using a new core base celeron (2C,4T) and it looks to be okay for 2-3 transcode. But the CPU was pegged 100%

If you have a microcenter around the AMD 8320e with mobo deal $99 is a great start for plex. The cpu mark is around 7500 so maybe 8 or so transcode streams http://www.microcenter.com/site/products/amd_bundles.aspx

I wish I would have read that before doing a bunch of testing. In secret, I was hoping to be able to get away with a cheap system like my wife's with an A8 something or other, but after some testing, it seems her system gets really crushed when you have 3 transcodes going (1080) at the same time. If I change the transcodes to 720 resolution, that CPU can do like 5 at a time. Either way, the system is pretty much unusable when running multiple transcodes.

The i7 I have in my system allows me to game on my system while supporting several transcodes without issue. I didn't test the i7 for how many at one time, but I routinely have five or six transcodes going while I game during the weekend.

So in the long run, I plan on just upgrading my own system while moving the existing system to a home plex server type box. Originally I was hoping to go with a lower power draw, but the CPU limit is an issue. If I change out the motherboard to something supporting on board video, and drop the 6950, I think this system would be fine for a home plex server with enough power to transcode many and a generally low power draw from the wall.

Before I kicked everyone off my server, it wasn't uncommon to see 6-8 people connected at once. Never heard any complaints... It was a VM over provisioned with 6cores off a Phenom X6 1100.

Now I'm thinking off pulling the 990FX and FX-8350 out of my gaming rig and moving that over to my hypervisor... and switching over to an i7 for the gaming rig. No real reason... other than I want an i7.

I'm running my plex on a xeon e5520 w/ 12 gigs ram. Have never run into a problem transcoding though I've never had beyond 4 streams going yet.