If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#31
|
|||
|
|||
Can ATX PSU blow the mainboard?
|
#32
|
|||
|
|||
Can ATX PSU blow the mainboard?
On Sunday, November 10, 2013 2:14:41 PM UTC-5, Flasherly wrote:
I then wrapped the PS with tin-foil, ostensibly, to determine I'd stopped spurious RF propagation from (somehow) entering the tape during backup processes. Nevertheless, the problem was solved by a tinfoil-wrapped PSU. If RF radiation caused a tape drive problem, that tape drive was defective by design. If a PSU was radiating that much RF, then that PSU was defective by design. Today's power supplies are not necessarily better than what powered 8080 based computers (before PCs). For example, the original IBM PC featured a 'Power Good' signal so that corrupting execution would not happen with defective power. I recently bought a used supply. Opened it. Discovered missing and required filters. Holes for those part existed. Jumpers were installed so that the manufacturer could cut costs by 'forgetting' required parts. Then I noticed other missing circuits. So I continued the investigation. Power Good signal for this recently built computer did not monitor voltages. 12 and 3.3 volts could be missing. Five volts could have been only three volts. And that Power Good signal would report all voltages OK. A major fubar existed because so many computer techs do not even know basic PSU functions. This 'defective by design' supply - promoted as an ATX supply - could explain why power loss corrupts data and other problems. An example of PSUs marketed to computer assemblers who 'feel' they are computer savvy rather than learn what a PSU does. How many 'know' unexpected power loss is destructive? Many saw a sudden power loss create other failures. Then assume power loss is destructive - using observation or hearsay as fact. Unexpected power loss never causes damage to properly designed equipment - not even disk drives. But many just know because they saw damage. Or learned from hearsay. Assumed a conclusion based upon observation. If enclosing a PSU in tin foil eliminates failure, then a 'symptom' is defined; not a solution. First find symptoms - especially those that are reproducible. Solutions come later after identifying a reason for that symptom. A defectively designed PSU? A defectively manufactured tape drive? Tin foil did not cure a problem; only cured a symptom. Since a PSU must not output major RF. And tape drives must make RF radiation irrelevant. Our current PSU standards are roundly superior to what existed before the IBM PC. And still many consumers buy PSUs that are inferior to old technology. A computer assembler (not the PSU manufacturer) is responsible for what is inside a computer's PSU. Many computer assemblers do not even know that. Properly designed PSUs are not damaged by the load. An overheated PSU must not cause computer damage. And would not cause a destructive surge. Early posters noted this. And also recommended a tool that every informed computer troubleshooter uses - a meter. So that problems are identified (with numbers) before fixing anything. A PSU damaged by its motherboard would be as defective as that PSU with a bad Power Good signal. |
#33
|
|||
|
|||
Can ATX PSU blow the mainboard?
wrote in message ... On Sunday, November 10, 2013 2:14:41 PM UTC-5, Flasherly wrote: I then wrapped the PS with tin-foil, ostensibly, to determine I'd stopped spurious RF propagation from (somehow) entering the tape during backup processes. Nevertheless, the problem was solved by a tinfoil-wrapped PSU. If RF radiation caused a tape drive problem, that tape drive was defective by design. If a PSU was radiating that much RF, then that PSU was defective by design. Today's power supplies are not necessarily better than what powered 8080 based computers (before PCs). For example, the original IBM PC featured a 'Power Good' signal so that corrupting execution would not happen with defective power. I recently bought a used supply. Opened it. Discovered missing and required filters. Holes for those part existed. Jumpers were installed so that the manufacturer could cut costs by 'forgetting' required parts. Then I noticed other missing circuits. So I continued the investigation. Power Good signal for this recently built computer did not monitor voltages. 12 and 3.3 volts could be missing. Five volts could have been only three volts. And that Power Good signal would report all voltages OK. A major fubar existed because so many computer techs do not even know basic PSU functions. This 'defective by design' supply - promoted as an ATX supply - could explain why power loss corrupts data and other problems. An example of PSUs marketed to computer assemblers who 'feel' they are computer savvy rather than learn what a PSU does. How many 'know' unexpected power loss is destructive? Many saw a sudden power loss create other failures. Then assume power loss is destructive - using observation or hearsay as fact. Unexpected power loss never causes damage to properly designed equipment - not even disk drives. But many just know because they saw damage. Or learned from hearsay. Assumed a conclusion based upon observation. If enclosing a PSU in tin foil eliminates failure, then a 'symptom' is defined; not a solution. First find symptoms - especially those that are reproducible. Solutions come later after identifying a reason for that symptom. A defectively designed PSU? A defectively manufactured tape drive? Tin foil did not cure a problem; only cured a symptom. Since a PSU must not output major RF. And tape drives must make RF radiation irrelevant. Our current PSU standards are roundly superior to what existed before the IBM PC. And still many consumers buy PSUs that are inferior to old technology. A computer assembler (not the PSU manufacturer) is responsible for what is inside a computer's PSU. Many computer assemblers do not even know that. Properly designed PSUs are not damaged by the load. An overheated PSU must not cause computer damage. And would not cause a destructive surge. Early posters noted this. And also recommended a tool that every informed computer troubleshooter uses - a meter. So that problems are identified (with numbers) before fixing anything. A PSU damaged by its motherboard would be as defective as that PSU with a bad Power Good signal. + A lot. Well said Chris |
#34
|
|||
|
|||
Can ATX PSU blow the mainboard?
|
#35
|
|||
|
|||
Can ATX PSU blow the mainboard?
On Saturday, November 9, 2013 7:31:53 PM UTC-7, wrote:
Bad capacitors do not cause destructive voltages. They don't cause them, but they can allow them by not filtering out voltage spikes from switching mode supplies or even spikes generated by sudden changes in load when chips change state, sometimes causing even excessive negative voltage spikes. All this was covered by Intel's application notes for even when they were still producing DRAM chips. |
#36
|
|||
|
|||
Can ATX PSU blow the mainboard?
|
#37
|
|||
|
|||
Can ATX PSU blow the mainboard?
On Monday, November 11, 2013 11:36:28 PM UTC-5, wrote:
They don't cause them, but they can allow them by not filtering out voltage spikes from switching mode supplies or even spikes generated by sudden changes in load when chips change state, sometimes causing even excessive negative voltage spikes. All those situations are made virtually impossible by how a PSU is designed. For example, a diode exists between different voltages so that one voltage cannot go negative in relation to another. But again, when buying PSUs that do not even provide spec numbers, then a computer assembler is 100% responsible for any resulting damage by that defective supply. An application note defines problems that must be made irrelevant by the design. Even spikes generated by switching circuits are quashed by another and required circuit that must exist. ATX standards even define voltages that each protection circuit must trigger. And again, when is that required function missing. Only a computer assembler is responsible for knowing that the supply has these many standard functions. Supply manufacturer need not provide them IF manufacturer specifications do not say so in writing. Two words that have no business in a PSU selection. Dollars and watts. Neither define a PSU as minimally sufficient - good enough. But can imply a defective supply - insufficient. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Blow-Out Cleanings | Steve Giannoni | General | 4 | December 12th 10 11:33 PM |
Blow Out Cleaning | Steve Giannoni | General | 10 | May 23rd 10 05:14 PM |
this will blow your mind!! | [email protected] | Homebuilt PC's | 0 | August 6th 08 06:57 AM |
Another Blow For the Dellsnots | Ted Zieglar | Dell Computers | 42 | October 29th 05 09:13 AM |
I can't blow it up!!! | gARY | Overclocking AMD Processors | 6 | September 6th 03 12:40 PM |