The 4100P's innards are shown in Figure 3, where you can see the AMD Geode LX800 CPU under the heatsink at the top of the board. The rather meager 256 MB of DDR400 memory sits on the SODIMM at the top right, which is inserted into a single connector. Although it's easy to change this memory, Thecus tells me that doing so will void your warranty, so you have been warned!
Figure 3: N4100 Pro inside view
Two Intel 82541 gigabit Ethernet controllers for the WAN and LAN port are at the lower left, with a 128 MB IDE Flash drive to their right. Just peeking over the top of the IDE Flash drive is an AMD Geode CS5536 Companion Device, which handles IDE, USB 2.0, audio and other miscellaneous I/O duties.
There is also a Phoenix E686 BIOS chip in one of the sockets and a Microchip PIC16F877A 8 bit microcontroller in the other. In case you're looking for the SATA controller, the Silicon Image SiI3114CTU PCI to 4 Port SATA150 is on the back of the board.
The motherboard plugs into the drive backplane via the black connector at top left. The backplane provides blind-mate connection to four 3.5" SATA drives, which are formatted using a standard ext3 filesystem. Drives up to 1 TB are supported (a PDF list of supported drives can be downloaded here).
The system is very quiet in operation. The only time I heard fan noise was during bootup when the system briefly revs the fan to full speed then ramps it back down. I measured power draw for a system loaded with four WDC WD1600AAJS-0 Caviar Blue drives (160 GB, 3 Gb/s, 8 MB Cache, 7200 RPM, provided by Thecus) with my trusty KillAWatt meter at 49 W active and / 26 W when the Disk Power Management feature (idle disk spin down) kicked in.
To achieve its lower price point, the 4100P dispenses with some of the 5200P's features. As noted earlier, you don't get the eSATA port. But more notably, the 4100P does not support iSCSI, which means you don't get the 5200P's Stackable feature, either.
The good news, however, is that the 4100P still delivers most of the other handy features found in its bigger siblings, such as online RAID expansion and RAID level migration. You also get Thecus' proprietary nsync system-to-system backup and ISO Mount feature that lets you share .ISO files stored on the 4100P as read-only share folders.
For media mavens, Thecus has included the same Mediabolic UPnP AV media server that was added to the 5200P. But the latest 2.01.04 firmware has added an iTunes server, as well (Figure 4).
Figure 4: iTunes Server
The Rescan Interval can be set to 1, 10, 30 or 60 minutes or 1 day and the MP3 Tag Encode control provides ISO, BIG5, GBK, GB2312, GB18030, EUC-JP, SHIFT-JIS, EUK-KR and UTF-8 alternatives. When you first enable the server, it silently and automatically creates an iTunes_music folder that is publicly browseable (the revised User Manual incorrectly identifies the folder as Music).
I found, however, that I wasn't able to access the new folder until I rebooted the 4100P. After a reboot, I was able to copy over a couple of folders of MP3 files, which iTunes found and played with no problem.
Another new feature is the Download Manager that supports HTTP, FTP and BitTorrent downloads. Figure 5 shows a Torrent and HTTP download in progress. You can start and pause downloads and remove them entirely, but can't edit them, even if they haven't been started.
Figure 5: Download Manager Status
I initially got an "Unable to Resolve Address" message when I tried to start the HTTP download, which I eventually traced to the fact that I had not entered a DNS Server when I manually entered the 4100P's IP address information. Once I did that and rebooted, the download started without a problem. Note, however, that the BT download did not throw an error under the same condition, but just showed no download activity.
Figure 6 shows the screen for adding a Download Manager FTP task. Note that it handles authenticated and anonymous downloads as well as active and passive FTP. Secure FTP isn't handled however. Each of the download methods, by the way, have bandwidth limiting controls.
Figure 6: FTP download task add
The BitTorrent add screen also provides Max (50) and Min (20) Peer Count controls and separate banwidth limits for up and downloading. The HTTP screen is the simplest, with just URL, destination folder and download bandwidth limits. So authenticated or secure HTTP downloads are not handled.
The Scheduled Power down feature that was added to the 5200P is also present in the 4100P. I tried it out and it worked fine, with the system drawing on 3 W while sleeping. With email alerts enabled, I found that the 4100P sent a message before shutdown and after startup. You also get a warning on the LCD panel that warns you that the system is shutting down, but not a warning beep.
The 4100P also has a Photo Server feature similar to the one on the N3200. I played with it a bit at it looks to be pretty much the same. The release notes say that support has been added for IP Cameras. But I could find no sign of it in either the web admin interface or the revised user manual.