[RESOLVED] Buying parts from overseas

At the moment I am looking at buying some kit from overseas. I am under the impression that all of the internal computing parts such as the main circuit card, secondary gfx cards, HDD, DVD-RW, and CPUs universally run on the same low voltage DC ouput (usually +12 V and +5 V) which is the same emanating from all PSUs, meaning the only difference in computing parts between AC and DC countries is the PSU itself, everything else is interchangeable.

This hopefully means that I should be able to buy any internal computing parts from any other country except the PSU which is the only part which has to accord with the local power standard be it AC or DC. Is my information correct, or are computing parts less universal than I think?

No, your first assumption is correct. They are universal. The PSU converts whatever the input power is... whether it be 125VAC, 250VAC or whatever. It's always AC though, no country that I know of uses DC voltage in a power grid because it's not only problematic, but cost prohibitive.

Whatever the input power, after a few transformers and voltage stabilizing circuits, it is converted to standard 12VDC, 5VDC and 3.3VDC power systems ending in standard connectors that connect to standard internal components. Computer parts stabilized in the early 90's with the explosion of "IBM PC clones". Aside from the occasional architecture upgrade such as ISA->VESA->PCI->AGP->PCIe or SDRAM->DDR->DDR2 or CPU socket du jour, it's all compatible.

Unless you have a very compelling reason, I suggest not to buy parts oversea because of the following reasons:
1. Quality: products imported into the US must pass certain quality standard.
2. Warranty/Returns: when that time comes, it is much easier to deal with a US based vendor than with some retailer off sea.
3. Buying oversea often means paying extra for shipping.
4. International shipments take much longer for items to arrive at your doorsteps than domestic.

Jenner, you are correct: DC (invented by Thomas Edison) was the US standard in the 1880s at a time when AC had not yet been invented, then it was gradually overtaken by AC, primarily, it seems, due to the availability of transformers until on "November 14, 2007, the last direct-current distribution by Con Edison was shut down" (http://en.wikipedia.org/wiki/War_of_Currents). Even so, and perhaps surprisingly, I still have my cash on DC to win the war over the longer term after the ATMs rise up and lead the charge to take over the world.

It is good to get confirmation regarding the universality of internal parts, as sometimes it is just not possible to get hard to find parts locally.