No Start? No Problem!

I am a first-time PC builder and started my project a year ago after I purchased your guide to building a dream PC. I have been collecting my parts over the past year and finally got a chance to piece them all together. The problem? My computer won’t start! I get a green LED on the motherboard when I turn on the power supply, but nothing happens when I push the case’s power button. Nothing starts: no case fans, no power-supply fan, no CPU, no videocards. What’s going on?

It’s great that you’re building your own rig, but you made a classic mistake. The warranty on components tends to be rather short, so you should always test your parts immediately. The Doctor understands that your situation didn’t let you test your gear right away, but keep this in mind for next time.

Now to your problem. The Doctor’s first suggestion, especially for rookies, is to ensure that you’ve connected the power switch correctly. Get out your motherboard manual and double-check that the wires for the switch are connected to the corresponding pins on the mobo. If the machine still doesn’t start, try directly shorting the two pins to POST the board—use the tip of a screwdriver to temporarily bridge the two. This will eliminate a bad power switch or wire on the case as a culprit. Also, make sure that the ATX12V and 24-pin main power connector are firmly inserted.

If you still don’t have any luck, try removing devices from the board one by one (make sure you power down the PSU first). After each removal, try restarting the machine. You might even have to unplug the hard-drive power cables from the board. Sometimes a pin in the power connector will get shorted against another, which can cause the PSU to immediately turn off.

30fps Sux

When running two 7900 GS cards in SLI, an AMD 4200+ CPU, a gig of RAM, and a Western Digital Raptor drive on a Foxconn NF4SK8AA motherboard, I should get jaw-dropping performance, right? I’m getting only 30fps in Need for Speed: Carbon with visual qualities set to high at a resolution of 1440x900. That doesn’t seem right! Lowering the qualities to low nets me 200-plus frame rates; medium gets me 50fps to 70fps. And at maximum? The car teleports. What’s going on?

Getting “only” 30 frames per second with the rig at the resolution you describe doesn’t sound all that unusual. The 7900 GS was introduced more than 18 months ago, and the Doctor has never known SLI (or CrossFire either, for that matter) to double any PC’s performance.

Having said that, you should make sure you’re using the latest drivers and that the GeForce SLI profile is set to use SLI (one of the options is to use a single GPU even when you have an SLI config). You might also experiment with the rendering options in the profile to see if one delivers better performance than the others.

One SLI, Two Different Cards?

Several months ago you were good enough to publish my question about SLI compatibility without actually answering the question, so let me rephrase. Whenever you talk about an SLI setup, you always describe a pair of identical cards in a fairly pricey system, which is certainly interesting to most readers of Maximum PC. But darker forces lurk in the readership—we’re cheap. Sure, we’ll build an SLI system but by starting with one card and adding a less-expensive card later. The cards will be compatible, but probably not identical. This will give us a performance hit, so my question is: How much of a hit?

Your question has the Doc scratching his head, Edward, but he’ll attempt to answer it—or at least what he thinks is your question. First, when you buy a videocard for the SLI rig you’re building, buy the best single card you can afford at the time—it’s better to get good performance today and better performance tomorrow than to leave yourself without an affordable upgrade path. As for your comment that you’ll buy a “compatible but probably not identical” card later, it doesn’t matter what brand the two cards are, as long as they both use the same GPU.

Remember, you can’t harness an 8800 GT to an 8800 GTS, if that’s what you’re inferring. And if you buy a second card that has a lower clock speed than your original, both cards (when SLI’d together) will run at the lower clock speed. That said, it’s in your best interest to pick a second card that’s identical to the first, and if not, at least go for one that shares the same specifications as the first.

Geek Squad Generalities

The last time I went to Best Buy, I was looking to purchase a new laptop. I asked a salesperson if I could split my hard drive and put XP on it. She talked to the Geek Squad and they said that it would be almost impossible to do that. The Toshiba laptop I was asking about was a top-end model. She also said that most laptops were like that and, thus, couldn’t run XP without a lot of trouble. Are they right?

The Doctor gets really annoyed with people who provide answers without even the simplest of explanations. The Geek Squad’s assessment is most likely correct, but they should have told you why. It’s highly probable that Toshiba doesn’t provide a Windows XP display driver for the notebook in question, and it won’t allow the GPU manufacturer (AMD or Nvidia, most likely) to do so, either.

The reasoning behind this restriction is that notebook manufacturers typically customize the display driver to support hot-key functions, power-management features, and suspend/resume behavior. The reference drivers that Nvidia and AMD develop don’t support these features, so they’re incompatible.

Nope. Nothing. You get nothing this month—no witty banter, no allusion to literature or songs. Zilch. The winter season has sapped the Doctor of his creativity, but thankfully, it hasn’t destroyed his resolve for answering your computer-related questions. Shoot those over to doctor@maximumpc.com.

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toshiba, sli, windows xp, ask the doctor, front-panel connector, 7900 sli

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