Thursday, March 17, 2011

The Necromancer

The title of this blog post also happens to be the name of the book I'm reading. Perhaps I've just been inspired to do a little necromancy of my own, but with less cadavers and more circuit board.

I'll explain; let's start with the fact that something's been bugging me. My desktop PC does not have a discreet GPU (video card).

You might be thinking, "WTF, and you call yourself an electronics freak?!" Well, you've got me there, but I do have reasons. One primary reason is that I'm not a gamer anymore. I do almost everything on this laptop nowadays, and I only took my desktop out of storage a few weeks ago so that I could get a decent VM box running in the basement next to my HTPC and my Cisco lab hardware.

However, my integrated GPU (despite it being a reasonably beefy AMD HD 3200) just ain't cuttin' it for some of the video processing and RemoteFX stuff I'd like to mess around with.

Fortunately, I have an NVIDIA 8800 GTS in a static bag that should do what I need it to do. Unfortunately, it's going to take a little more than me popping this sucker into my PC to get it running.

Problem #1: The graphics card does not have an enclosure for the heat sink; the fan cannot circulate air to keep it cool.

Problem #2: It's damaged goods. (Okay, I lied, the card isn't entirely dead. But someone who brings sick people back to life is a doctor, and that's a lot less fun than being a Necromancer!) It displays bands of pixels vertically across the screen that are visible during the boot process, which means it's a hardware issue, not a driver problem. Additionally, it usually won't boot into Windows, causing the system to hang when the operating system is starting up. On the rare chance it does make the boot into Windows, graphics are horribly distorted.

So, I'm screwed, right? Hell no! I wouldn't pass up an opportunity like this! Read on to see how I got this old workhorse running again.

Alright, so Problem #1 isn't too bad, right? All I've gotta do is build something that lets the centrifugal fan on the 8800 GTS push air through the fins of the heatsink instead of just stirring it around uselessly. Besides, this isn't my first time building oddly-shaped fan enclosures for electronics equipment. This time it ain't gonna be pretty though. Since this beast has hardware issues, I'm going to stick with function over form until I know I can beat Problem #2.

After a few rough measurements and half-an hour with an exacto knife, some cardboard off a Radio Shack box, and everyone's favorite silver tape, here's what I've got:

Okay, so it probably won't melt now. The only problem that remains is that it's already screwed up. So what am I going to do to fix it? Melt it.

Wait wha...? And we just went to the trouble to make sure it won't melt? Yep. Time to work some black magic. All it takes is an oven, a cookie pan, some aluminum foil, and the blood of a virgin maiden. Okay, that last one is optional... I went without.

Here's what you do. Set your oven to 385 degrees. Now remove every removable plastic component from the graphics card, and get out the cookie sheet. Now find a way to position the video card so that NO electronic component or solder point comes into contact with the cookie sheet. Any major components on the board should probably be face-up or they may fall out when the solder melts. When I've done this in the past, usually I've made 4 little balls of aluminum foil, placed them at the corners of the PCB, making sure they don't touch any solder or components, and balance the video card on top of them.

Now I chose to turn this graphics card upside down, resting on the heatsink. I then crammed some aluminum foil between the fins of the heatsink and propped it up to prevent it tipping forward. I also removed the fan after taking the picture below (I forgot to take a new picture after taking it off). Basically, don't do it like how I did; I was a little careless (mostly 'cause this card was a freebie from my little brother).

Carefully place your video card in the hot oven, making sure everything is in place before carefully closing the door (a slam might drop your card onto the cookie sheet and if you don't notice, you'll have a paperweight in a few minutes!)

Wait 10 minutes and peek inside. The solder points on the board should look extremely shiny, like chrome. If they don't, it might need another minute, but I wouldn't let it go for much more than 12 minutes. Carefully remove the cookie sheet with oven mitts being extremely careful that the video card does not fall onto the cookie sheet or get jarred. The reason for caution is twofold; the video card is very hot and you may burn yourself, the solder on the board should be melted, which is also a burn hazard, and the components of the board are now loose and may fall off the board if jolted or touched. The solder cools quickly too... if something falls out, you'll probably need a soldering iron to put it back in (trust me on this one!)

Wait at least 30 minutes for the card to cool before getting all the plastic bits reattached and the graphics card popped back into the PC. After I got my new fan enclosure put on and the graphics card installed, I booted up the PC. No vertical bands of doom! Windows booted as well, another good sign, and I proceeded to install the graphics drivers. While that was going, I checked the rear vent on the card and felt a good flow of warm air coming out. I also felt the sides of my fan enclosure, slightly warm to the touch, but not hot. Below is a picture I took of the screen once I'd gotten the drivers instead and the resolution cranked up. I'm going to run it through some benchmarks to see how it holds up but I did load up Mass Effect with maxed graphics and resolution and pushed the card through a thick firefight without observing any graphic anomalies or artifacting. At this point, I'm ready to declare success!

This technique is something I learned years ago from somewhere on the internets and I've baked several video cards since. Some were completely non-functional, some had glitches and errors. Only once was it unsuccessful in bringing a card back to life, and that was one that had been baked before quite a while prior. Most hardware issues with graphics cards arise from connection issues in the circuitry forming after the repeated heating and cooling (which causes expansions and contractions that can break those connections apart). This process is known as "reflowing" the card, because the solder is remelted and cooled, re-establishing those connections.

If you've got a card with hardware problems, there's no reason not to give it a try... unless of course you're worried that your housemates will think you've lost your mind when you don an apron and oven mitts and start popping electronics-laden cookie sheets into the oven.

But hey, so what if they confuse necromancer with mad scientist? ;)

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