New Custom Built Computer

[helen]

Re: Konaguy Has Returned From The Dead

If I had to guess poor quaility capciators might be the reason why your power supply failed.

[Konaguy]

Re: Konaguy Has Returned From The Dead

What precipitated this whole thing was hearing this big whoosh sound coming from my computer. There was dust on the power supply, I admit...I suspect
something happened to the fan that caused the power supply to fail.

[Pomai]

Re: Konaguy Has Returned From The Dead

A common component failure with CRT monitors, whether computer or TV is the flyback transformer. My friend's iMac monitor failed at about age 4. After researching online on other iMac failures, the symptoms his had - arching sound and no picture - was caused by a faulty FBT. Surprisingly as old as my iMac is, the CRT is still sharp and bright.

We bought a 32" Zenith CRT Television a long time ago, and within a year it started making arching sounds and the picture would flicker. I asked a friend who repairs TV's what the deal was. He said most likely moisture was getting between the FBT's anode boot, where it attaches to the back of the tube. He said to try putting a bead of silicone between the boot and the tube. Sure enough, it WORKED! That tv went on to lead a long and healthy life.

[craigwatanabe]

Re: Konaguy Has Returned From The Dead

I'll bet that whoosh was either the CPU fan or the Power supply fan suddenly cutting loose from caked on dust. The fans create a higher than normal amp load on the psu when they're on but stuck. As the fan resists the motor's attempt to run it builds up current draw until the PSU either fries or WHOOSH and suddenly the fan is free and all that dust is blown out like a leaf blower.

In power supplies, the weak link is the bridge rectifier which is basically four diodes in a wheatstone bridge configuration. The rectifier converts AC into DC. The large filter capacitors provide the damping to smooth the rectified AC into a clean DC signal.

Once the voltage is stabilized into a clean DC voltage, different voltage regulators reduce it to individual voltages such as your +30vdc, +12vdc, +5vdc and -5vdc outputs that are common in most of today's computer PSU's.

Some of the more complicated PSU designs are Trygon PSU's which regulate the AC signal then complex rectification and filtering is done to provide the DC signals needed without the need for a transformer. Trygon PSU's allow for higher amp outputs because the voltage regulation is done prior to rectification and quicker switching as there is no ratio drop or center taps like conventional PSU's. This allows the rectifiers to push higher amp loads thru instead of at the gate.

The problem with Trygon PSU's is that if the regulators fail, 120VAC is sent thru the rectifiers and ultimately to the final destination which could be your hard drive etc.

On today's standard PSU's that are resistant to frying motherboards, they use breakdown diodes that will literally open their contacts if the voltage they're limiting surges pass their limits. Kinda like a fuse for voltage unlike a standard fuse which is for amperage protection. The cheaper PSU's don't incorporate any protection such as breakdown or self correcting Zener diodes.

As for CRT flyback transformers, yeah they go out but be careful about using standard silicone sealants. Flyback transformers require a higher value insulation when sealing the anode boot. Better to use an anode dope that has a higher insulation value and is recommended for high voltage leaks. Eventually the arcing will eat thru the silicone and the problem will come back.

[Pomai]

Re: Konaguy Has Returned From The Dead

Continuing with these "Frankenstein" jobs here...

When my friend's iMac flyback transformer fried, he contemplated replacing it himself, but went another route after reading about the danger of high voltage in the uncharged CRT. Not to mention an amateur D-I-Y "tech" attempting to go anywhere near a motherboard with a soldering iron.

Instead he simply disconnected the (internal) 15-pin cable that leads to the video portion of the iMac and plugged in a cheap, used external PC monitor using a Mac-VGA adapter. Ran that for a while then got sick of looking at the bulky, dead monitor "shell" sitting on the floor. Eventually removed the motherboard/PSU/HD/CD-rom tray out and stuck it all in a generic mini-tower case. His kid still uses that iMac to this day.

[Konaguy]

Re: Konaguy Has Returned From The Dead

I'll bet that whoosh was either the CPU fan or the Power supply fan suddenly cutting loose from caked on dust. The fans create a higher than normal amp load on the psu when they're on but stuck. As the fan resists the motor's attempt to run it builds up current draw until the PSU either fries or WHOOSH and suddenly the fan is free and all that dust is blown out like a leaf blower.

I had just cleaned the CPU fans..So I eliminated that as a culprit. The power
supply fan did have some dust on it.But I would be surprised it was enough to
overload the fan causing it to Whoosh.

[Konaguy]

New Custom Built Computer Pictures

I finally got around to take pictures of my custom built computer I bought
recently. :

The fine print :
1GB RAM
80/40GB HD
2.8Ghz Celeron Processor
6 USB slots
16X DVD-RW/ROM drive
Windows XP Home

[Konaguy]

Re: New Custom Built Computer

http://www.dslreports.com/forum/rema...art=0#16236611

I really did get roasted. But I'm happy with what I got

[adrian]

Re: New Custom Built Computer

That's one big heatsink fan.

My dual core processor's heatsink isn't even that big (and I'm using a mATX motherboard). So, got any 3dmark scores?

[shaveice]

Re: New Custom Built Computer

just came across this thread today. interesting stuff. craig, are you saying that you custom build computers for friends or are you just stating how much it would have cost if you had been given the task?

(by the way, i'm not in the market right now. got my pc custom built by a friend about 2 yrs ago and it's still humming along beautifully....)

[craigwatanabe]

Re: New Custom Built Computer

just came across this thread today. interesting stuff. craig, are you saying that you custom build computers for friends or are you just stating how much it would have cost if you had been given the task?

(by the way, i'm not in the market right now. got my pc custom built by a friend about 2 yrs ago and it's still humming along beautifully....)

I do build them for friends at cost only because I really do enjoy building computers. Sometimes they can be a headache like the one build involving an ECS mobo and an Nvdia graphics card. Lotsa conflicts on that build but I finally got everything to work by updating all the drivers for everything that was installed.

Right now I'm posting this response on a friend's computer he needed cleaned out. It was running slow so I ran CCleaner to take care of defunct and unnecessary registry keys then I ran Ad-Aware and Spy Bot Search and Destroy to take out the malware. After doing a disk cleanup, scan disk then defrag, this computer is back to "fresh install" speeds with a cleaned up registry and all spyware removed.

These were simple maintenance actions anyone can do with free software available on the internet. However I've had friends up here on the Big Island pay over $300 to do the same thing I just did for free. They tell me, "Well $300 is still cheaper than to buy another $1200 computer" Hmmm I tell them,"I wouldn't have paid $1200 for that thing" cuz it's only worth about $500 in parts.

That's when the eyes open up and the realization that it's not really that hard to build one yourself nowdays for about half the cost of buying one off the shelf.

[Pomai]

Re: New Custom Built Computer

Has anyone ever seen 'ready-to-assemble' computer kits?

Meaning the same as preconfigured factory-built systems, but in unassembled form. Kinda' like a model kit.

Of course you can order everything in parts, such as Craig recommended from NewEgg.com, but you still need to have some know-how in which components are compatible and will work together with optimum performance.

It'd probably be tough to back-up warranties for such a thing, as amateur DIY'ers could possibly fry something in the build process.

Still, if RTA computers could be sold for one to two hundred dollars cheaper than built systems, I'd opt for it.

[chriscollado]

Re: New Custom Built Computer

You can buy computer parts to build you're own computer. Go to newegg.com they are the best for onling computer part shopping. If you build from the ground up you'd better know what you are doing. If not you will waste alot of money. Do research first. 1. pick your case 2. pick your motherboard (make sure it will fit in the case) 3. pick your processor(make sure it is compatable with your motherboard 4-? pick Hard drive (must also be compatable with the motherboard) dont buy a IDE hard drive and Have a motherboard that only supports SATA. make sure you buy the correct memory for the processor and motherboard.... research research research..

[chriscollado]

Re: New Custom Built Computer

sorry .. i just realized i posted alot of redundant crap.. I'm an IT specialist and I'd still rather buy an already made computer. I don't have the time to mess around with one I have to build myself. Listen to Craig. He is pretty smart with this stuff. I deal mostly with mail servers domain controllers and file servers. I try to stay away from the hardware aspect.. I hate it.

[shaveice]

Re: New Custom Built Computer

I do build them for friends at cost only because I really do enjoy building computers...

. . . . . . . . . . .
you've got some lucky friends

i can't justify paying for a new, custom pc right now since mine is working fine, but when the time comes i wouldn't mind getting your suggestions on what parts to buy. i use my computer as a tool everyday but i never really spend anytime learning about what new and improved parts are available, etc. so your input would be invaluable.