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Holy shit.

8 amps through the microUSB port is just stupid. I'm guessing the power supply circuit isn't overheating, it's the microUSB connectors that are overheating.

Telling people it's okay to use any charger but the one it comes with only works because the Chromebook won't try to suck 8 amps over a connector typically rated for 1.8 amps.

No fucking wonder why Apple launched Lightning instead.

http://www.molex.com/webdocs/datasheets/pdf/en-us/0475901001_IO_CONNECTORS.pdf

Just thought of one more thing. Docs aside, I really didn't like the use of terminal blocks to make the shielded wire to motor connection, so I actually used some of the large molex that you see on PC power supplies.

I aborted that, am running without the shilded wire for now (its still a bit of a mess but printing beautiofully anyway). So I decided to break down and place a mouser order for some of these:
http://www.molex.com/molex/products/datasheet.jsp?part=active/0430250408_CRIMP_HOUSINGS.xml

of the appropriate size, and their mating parts/pins etc, and then I will finish making my wiring pretty.

less then pci-e X4 is poor for video cards and useing one maxes out the BUS. Why not just use External PCI Express and get full pci-e speed.

http://www.molex.com/molex/products/family?key=external_pci_express_pcie&channel=products&chanName=family&pageTitle=Introduction

The magnetics in question aren't to hold the connector in like those in a Mac power cord, but rather the tiny transformers that are required for Ethernet differential signal isolation/transformation.

Hey, thanks for the explanation/link. Haven't had time to look it up lately.

also see http://www.molex.com/mx_upload/family/magnetic_modular_jacks/hypejak.pdf

The magnetics in question aren't to hold the connector in like those in a Mac power cord, but rather the tiny transformers that are required for Ethernet differential signal isolation/transformation.

external pci-e is in the works and does not have the over head at Thunderbolt has and will not be Intel locked.

http://www.zdnet.com/blog/computers/look-out-thunderbolt-external-pci-express-spec-being-developed/6220
http://www.molex.com/molex/products/family?key=external_pci_express_pcie&channel=products&chanName=family&pageTitle=Introduction
http://www.andovercg.com/datasheets/molex-74546-0813.pdf

Thunderbolt may be good for external HDD's and other high data stuff. But for PCI-e add in cards and video cards better to go with pci-e also the mac's with on board video have like 8-12 unused pci-e lanes any ways so why not run a video card off of them as 1 video card just maxes out the Thunderbolt bus and still does not let it hit it's full power. Maybe in 2013 you can have a mac mini with a good cpu and a pci-e box with a good video card in it.

Besides the 'wood screws', the other claims about this card are incredibly suspect. 1) The connectors not showing through are hard for me to buy from just looking at fuzzy pictures as there are about 8 pixels for each of these solder points to juge from. You don't necessarily see the pins protruding way out on some parts. 2) Some of those parts with "missing" connectors could be surface mount. Like this molex power connector.

Why hasn't anyone implemented external PCI Express? One of the coolest things about PCIe is that you can put it on a cable with no extra work, due to its serialized and point-to-point nature.

PCIe external connectors have been spec'd for over a year now, in widths from x1 to x16. The x1 connector has 18 conductors in about a DSub-9 size, with the usual screw-locking features.

And we know PCIe works at high, sustained data rates. And it's an Intel-backed standard, so no motive for them to "forget" to put it in their chipsets like they did with FireWire. Also, it would be trivial to make a PCIe board that took its x1 port and just wired it straight to the back panel.

So what's stopping people?

Also, I believe that the original specification for drive power connectors called for an AMP part number, although Molex may be making a compatible part nowadays.

In response to your quotes I went and looked on Molex's site. Since we're talking about video ram here, I decided to look up the spec for the SGRAM JEDEC 144 SODIMM modules used on video cards.

The spec says that the contact resistance is 70 milliohms max, and at a test frequency of 100Khz the stray capacitance between pins is a max of 2 pF.

What this all boils down to is that it's really irrelevant.

All the communication lines of boths DIMMS (have 2 sitting in front of me) and SGRAM SODIMMs are loaded with 10 ohm resistor arrays. This means that any stray capacitance or resistance is overcome by the 10 ohm loading.

They are already doing high speed clocks to DIMMs, close to the speeds that video cards are doing on board.

The REAL crux is that it's A LOT cheaper to manufacture the board with the components already attached. Your footprint is smaller too.

Refer to these documents for further information:

JEDEC SGRAM 144PIN SODIMM video ram specification

Molex SGRAM socket specification

I appreciate the healthy skepticism. I think all of us agree that modular RAM could be added to the system. However, there are engineering tradeoffs. By soldering the RAM directly to the board the signal quality is better and therefore timing can be sped up. I went all over the net looking for specific proof that connectors, especially DIMM connectors add capacitance. The best I could find was one from Molex, one of the connector manufacturers themselves. They state in their Product Specification PDFs (hope that nasty generated link works) that the connector (part# 71736-0011) adds 1pF of load at 1MHz with a 50 Ohm impedance. Now as you increase the speed of the bus to say... 100MHz, 200MHz, etc.. it gets worse. Sorry I couldn't find a better link for ya.

Anyway... yes, engineers could design in removable RAM, but consider this. The RAM types are changing all the time! You would pay an extreme premium for the specialty RAM because it would vary from manufacturer to manufacturer, card to card, even model to model. The memory types are changing all the time and getting faster all the time and thus the connectors would have to change to keep up with the speed. For now it really is just easier to solder it on. Besides that card of yours will be worthless in two to three years anyway... ;)

Hope that helps dispel some of the skepticism.

JOhn

Each SilentDrive requires a 5.25" bay, so if you're using a real hotswap RAID enclosure, rackmount or otherwise, the SilentDrive is not an option. In that case, I'd invest in a rack cabinet and glue acoustic foam tiles over the entire surface. ;-)

The same outfit also makes low-noise active and (no-noise) passive CPU heat sinks, and at one time they also made quiet power supplies.

When Silent Systems was independent, they had a low-volume retail business. Unfortunately, Molex apparently doesn't sell these products at retail, and the distributor mentioned on their pages doesn't list them among the products they sell either. Does anyone know where to get these, or a similar product?

Once your hard drives have been muffled, the next most annoying noise is the power supply. PC Power and Cooling's Silencer 275 (rated at 34 dB) is a big improvement over typical power supplies.