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| Thread ID: 85846 | 2007-12-24 03:34:00 | 8 Y/O COMPAQ Presario Question | SurferJoe46 (51) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 624210 | 2007-12-24 03:34:00 | Got a freebee in the form of a Compaq Presario 5BW Desktop PC, Intel Celeron, WinME, about 384MB RAM, single HDD . . etc . . etc . . . I thought I had a dead PSU . . . took it out and metered all the outputs . . . from BLACK to PURPLE . . there's a 5 . 03VDC output . Any BLACK will do . . . I think it's pretty much the whole system ground . . . . Anyway . . . I DO believe the CMOS is dead-dead-dead . . . will get one tomorrow . . . . But in the meantime . . . . here's the question . Can I not get this to boot or even turn on at all unless there is some CMOS charge? It just sits there and ignores me . Frustrating in that I have had bad and dead CMOS batteries before and I could at least get a black or BSOD screen somehow . Nada! :badpc: I tested the ON-OFF pushbutton . . it has a good contact . . but somehow I think that PURPLE 5Volt is just waiting for some sort of signal to turn the whole thing on . . Right? |
SurferJoe46 (51) | ||
| 624211 | 2007-12-24 03:58:00 | ......and I forgot to say..."Guess what? I'm gonna try another stab at Linux...again...stand by all! | SurferJoe46 (51) | ||
| 624212 | 2007-12-24 04:28:00 | I would say if its the CMOS battery, and its flat, it wont turn on, since there's no settings for the BIOS. And, it wouldnt know what its looking at / for. | Speedy Gonzales (78) | ||
| 624213 | 2007-12-24 04:40:00 | Yeah..but not even a splash or a flicker in the CRT? Will go out and buy a new CMOS battery tomorrow...it's about 9PM, Sunday 12.23 here now. Hahahahahahahah...my question is #4 on Google Search already! Wow..them slurp spiders are fast! |
SurferJoe46 (51) | ||
| 624214 | 2007-12-24 06:01:00 | Well-l-l-l-...just got back from all-night Wal-Mart and got the CMOS battery...but it's still untalkative. | SurferJoe46 (51) | ||
| 624215 | 2007-12-24 06:04:00 | I would open the case and see if everything is still connected. Do the cd/dvd's open if its got any?? |
Speedy Gonzales (78) | ||
| 624216 | 2007-12-24 06:12:00 | I would open the case and see if everything is still connected. Do the cd/dvd's open if its got any?? Nothing works..I wonder again about a dead PSU...there's nothing anywhere but that purple-to-black voltage of 5.03 or so.... No nuttin'! |
SurferJoe46 (51) | ||
| 624217 | 2007-12-24 06:45:00 | . epanorama . net/documents/pc/pcpsu_connector . html" target="_blank">www . epanorama . net If this were me the first thing I would do after checking the obvious, wires, plugs, sockets, mains power where it should be, is to change the 1uF 50V electrolytic caps that are part of the switch-on multivibrator circuit in the PSU . In this part of the circuit they are always 1uF 50V, there are two of them . They are nearly always positioned near to the heatsink for the Xistor/Fets power switching devices, they should be black in colour which means hi-temp environment capability . If you try this Joe you must discharge the main power capacitors with a 100Kohm resistor each time you power up and then switch off, because the original resistors for this purpose are nearly always open circuit, you should replace them as well, I presume you are familiar with the operation of a multi-meter having read all your postings about repairing motor vehicle electrics etc . Be careful, those PSU main smoothing capacitors after the mains bridge rectifier can deliver a nasty shock for days after the unit has been powered down if they are not discharged by you if the original resistors are open circuit . You will need a small soldering iron and reasonable fine motor skills to do this job successfully and it may not be the fault but it has been a lot of the time when a computer does not switch on/only runs sometimes/runs after being switched on/off a few times but there is no obvious damage like blown fuses, burnt circuit boards etc . This is a fairly common recognizable failure mode, I have fixed a number of them . There is a similar common recognizable failure mode on Monitors as well which is the same fault condition ie no observable damage but does not run . |
zqwerty (97) | ||
| 624218 | 2007-12-24 07:17:00 | I'm thinking here that I might try to find another PSU...any ideas? It's a P-III Celeron...and the original PSU is 400Watts according to the sticker. |
SurferJoe46 (51) | ||
| 624219 | 2007-12-24 07:35:00 | Read what the model is on the side of the old PSU and google it, must a supplier close to you that has an equiv or recycler that can let you have one for a song, although likely that anything of the age that yours is will have a similar fault to the one I described. | zqwerty (97) | ||
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