Och, it be borken. No, no you read right. Borken. If you’re computer’s been playing tiddly-winks with your sanity, type some text and send it in. No doubt Mr Rutter will be able to prescribe you something, and, if you happen to be clinically mental, you’ll receive the wunderbar Logitech MX 500 mouse. Word.
IOOTM: Purposeless pin?
I: I suffered that horrible sinking feeling in the pit of my stomach the other day. You know the one you get when you break a pin on the IDE connection on a part that you can probably never buy again. Worse still, it was on a friend's computer! I managed to destroy pin 1 on a super-floppy drive. However, the next day, to my great relief, when I hooked it up anyway - it worked!
I vaguely remember from my college days that many of the pins don't actually do anything, but have no idea which ones are important. Can you please tell me the pin assignments for IDE?
Liz Braddon
O: Well, every pin does something (except for pin 20, which is used for keying; that one's only mechanically functional), but seven of 'em are earth pins.
You didn't cut one of those; you cut the Reset IDE pin, which is what's used to soft-reset the drive. Soft-resetting isn't often needed. By default, it happens when you reset the PC, and it can cure a drive that's been left in an insane state by a bad driver or some similar mishap, but a drive that isn't currently nuts will work fine if you reset the computer without resetting the drive as well. You can always reset your drives, whether or not they've got a pin 1, by turning the computer off and back on.
You can find the standard IDE connector pinout here:www.bbdsoft.com/ide.html
Nuclear computing
I: I was wondering, wouldn't it be great if we could use heavy water for cooling a PC down? Wouldn't that work? Isn't heavy water used in reactors? Why can't we apply the same method with the humble PC?
elmo198
O: Heavy water in a PC liquid cooling system would work no better than regular water, but it'd be way, way more expensive.
Heavy water is, chemically, practically identical to ordinary water. It [i]is[/i] heavier; a heavy water ice cube will sink in normal water. But apart from that, and a slightly higher melting and boiling points, all heavy water does is block stray neutrons better than regular water. That's why it's used in some breeder reactors to make plutonium from uranium; fast neutrons are slowed down enough by bouncing off heavy water nuclei that uranium nuclei can then capture them.
Neutron slowing isn't a high priority for PC water cooling systems, and heavy water costs thousands of dollars per litre. Furthermore, if you try to buy some, people are apt to think that you're considering turning a city into a smoking grease spot. All this makes heavy water less than totally interesting as a PC coolant.
Why so slow?
I: Why do ATA HDDs spindle speeds top out at 7,200rpm, while SCSI drives go to 15,000rpm? Surely the interface isn't a bottleneck, because today's ATA drives can't get anywhere near filling the bandwidth offered by ATA/100/133, and now SATA. Is it just that HDD manufacturers want to give their faster drives a SCSI interface so they can justify slugging people an extra $350 for them?
David Allen
O: There is an artificial market segmentation thing going on here. Faster rotating drives need better motors and bearings, but there's no reason at all why that level of engineering couldn't be applied to ATA drives. And, as you say, current ATA interfaces have bandwidth to spare.
The dead hand of marketing isn't the only thing to blame for the absence of high rotational speed ATA drives, though. Drives that spin much faster than 7,200rpm run hot enough that they're not happy in the average case.
Hard drives get hot because there's air inside them; air friction on the spinning platters makes heat. 10,000rpm-plus drives make enough heat that they need extra cooling.
If you've got unusually good case ventilation and/or an unusually low ambient temperature, you can run top-spec SCSI drives without adding anything more to keep them cool. But if you drop those same drives into an ordinary mini-tower case, they're likely to die before their time.
Manufacturers therefore want to keep high-rpm drives out of the mainstream. They'd get showers of warranty returns if they didn't.
Inadequate aperture?
I: I recently bought a GeForce4 Ti4200 card with 128MB DDR-RAM. My motherboard is an ASUS CUSL2-C with a Pentium III 933MHz that is not being overclocked (shameful I know). The problem I have found is that my motherboard only allows a max AGP aperture size of 64MB. Does this mean I am losing half the memory performance of my video card? How much of a performance increase would I see if I were able to increase the AGP aperture size?
Philip Choo
O: No, you're not losing any performance. A larger aperture size would give you a barely measurable speed increase, if it gave you any at all.
The AGP aperture size sets the amount of system memory that can be shared with the graphics card, using the AGP bus to allow the card to behave as if it had more memory than it does, and store textures in main memory when it runs out of RAM of its own.
Even if you're using AGP 8x, though, main memory via AGP will still be quite a lot slower than video card memory. If you actually [i]use[/i] AGP texturing while you're playing a game, performance will drop substantially.
Some video card and motherboard combinations misbehave with default AGP aperture settings, causing 3D games to crash. In those cases, you need to set the aperture size to some particular size, usually 64 or 128MB. Setting the aperture size larger than that will give you a tiny performance gain, at best; with modern video cards that have tons of onboard memory, little of the assignable memory is ever likely to be used.
Setting an aperture size larger than the amount of system memory you have shouldn't ever help (you can't share memory that isn't there. . .), but it does apparently do something, for some systems. 'Something', though, doesn't mean 'anything you'll notice without running benchmark programs'.
Setting a small aperture size, by the way (32MB or 16MB), will disable AGP entirely, and leave your video card behaving like a 'AGP 0.5x' PCI card.
Basically, if your system doesn't have any problems, don't worry about the AGP aperture size.
X-compatibility
I: I am planning on buying an Asus A7N8X Deluxe mainboard and an AGP-V8640 Ultra Deluxe video card, but I have read in places that AGP 4x cards are not compatible with AGP 8x mainboards. Is this correct? If I buy this combination of mainboard and video card will I end up with a very expensive paperweight?
Chris Rutch
O: While it's hardly unknown for some motherboards to dislike some video cards, there's no compatibility barrier between 8x and 4x. Stick a card that can only manage 4x in an 8x slot and the motherboard should just run it at 4x, the same as happens with 2x cards in 4x motherboards.
Precious metalStatus: UX-UIDL: 341726630
I: I'd like to see some information regarding some snazzy Aluminium cases verses the old beige boxes. Maybe some temperature measurements with boxes of very similar dimensions, and even cover any air holes to ensure a fair trial (although they're part of the case, so maybe leaving them open would be an idea
Issue: 137 | June, 2012