Help Please, I'm lost

[irishtxboy]

I have an older compaq presario 4090us It has been randomly shutting down and sometimes restarting sometimes just the lights on the front of the case and PSU fan are on. I have replaced the power supply and that worked for about 12 hours, I've ran MemTest and everything reports fine, I've ran the diagnostics from the HD manufacturer every thing comes back as good, I even pulled the two memory cards and switched them around it seemed to speed up my computer but hasn't stopped the problem. I disabled automatic restart and when ever it dies I just get a black screen with the case lights and PSU fan on. I am completely lost and any help would be appreciated. Here are the specs from my system.

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Operating System               
Windows XP Professional Service Pack 2 (build 2600)
System Model              
Compaq Presario 5108US 470013-873 W21CDBCB
System Serial Number: 2222JD551111
Enclosure Type: Mini-Tower
Processor a               Main Circuit Board b
900 megahertz AMD Duron
128 kilobyte primary memory cache
64 kilobyte secondary memory cache               
Board: Compaq 0708h
Bus Clock: 100 megahertz
BIOS: Compaq 786K3 07/26/2001
Drives               Memory Modules c,d
30.01 Gigabytes Usable Hard Drive Capacity
24.42 Gigabytes Hard Drive Free Space

HL-DT-ST CD-RW GCE-8525B [CD-ROM drive]
3.5" format removeable media [Floppy drive]

QUANTUM FIREBALLlct20 30 [Hard drive] (30.02 GB) -- drive 0, s/n 053112743751, rev APL.0900, SMART Status: Healthy               248 Megabytes Installed Memory

Slot 'DIMM1' has 128 MB
Slot 'DIMM2' has 128 MB
Slot 'DIMM3' is Empty
        Local Drive Volumes
        
            
c: (NTFS on drive 0)       30.01 GB       24.42 GB free
        Network Drives
        None detected

Controllers               Display
Standard floppy disk controller
Primary IDE Channel [Controller]
Secondary IDE Channel [Controller]
VIA Bus Master IDE Controller               S3 Graphics ProSavage 8A26 (Microsoft Corporation) [Display adapter]
Proview 17.1 [Monitor] (17.1"vis, s/n F5WY5C119011U, December 2005)
Bus Adapters               Multimedia
VIA Rev 5 or later USB Universal Host Controller (2x)               VIA AC'97 Audio Controller (WDM)
Communications               Other Devices
Compaq Data Fax Modem

            
CNet PRO200 PCI Fast Ethernet Adapter
 primary        Auto IP Address:       192.168.1.10 / 24
      Gateway:       192.168.1.1
      Dhcp Server:       192.168.1.1
      Physical Address:       00:08:A1:1C:57:9C
 
Networking Dns Servers:       207.71.36.232
207.71.36.229
              Standard 101/102-Key or Microsoft Natural PS/2 Keyboard
PS/2 Compatible Mouse
USB Root Hub (2x)
Virus Protection [Back to Top]       
AVG 7.5.441 Version 7.5.441
    Realtime File Scanning On
      

[GX1_Man]

So whatever killed the first power supply got the replacement one as well?

[ale52]

Sounds like you have a short somewhere in the system.  Can you remove everything from the case, connect it up and try it that way?

Alan <><  

[irishtxboy]

Sounds like you have a short somewhere in the system.  Can you remove everything from the case, connect it up and try it that way?

Alan <><  

This got me to thinking, and in talking with my wife I found out she couldn't get her camera to show up when she plugged it in to the USB ports. So could the USB ports be bad and causing this? if so since I beleive they are part of the MOBO does this mean I need to replace the MOBO?

[soybean]

What power supply did you get when you replaced the power supply?  How much did it cost?   Cost generally gives some indication of quality.

[irishtxboy]

What power supply did you get when you replaced the power supply?  How much did it cost?   Cost generally gives some indication of quality.

It was the compaq replacement, this dang thing has a special mounts, It ran $40

[soybean]

I have an older compaq presario 4090us It has been randomly shutting down and sometimes restarting sometimes just the lights on the front of the case and PSU fan are on. I have replaced the power supply and [highlight]that worked for about 12 hours[/highlight], ...

Please clarify.  Does it still start up and run for awhile and then randomly shutdown, etc., or does if not start at all now?

Besides the fan in the power supply and the CPU fan, how many fans do you have installed in your computer?  Where are they?  Which direction are they moving air?

Did you make any hardware changes (excluding the power supply) before this started happening?  Add a video card or other new components?  Have you ever removed the CPU fan and heatsink?  

Do have any way now of getting temperature readings for the CPU?  If not, I suggest you download SpeedFan and install it and see what info it will produce for that computer.

[irishtxboy]

I have an older compaq presario 4090us It has been randomly shutting down and sometimes restarting sometimes just the lights on the front of the case and PSU fan are on. I have replaced the power supply and [highlight]that worked for about 12 hours[/highlight], ...

Please clarify.  Does it still start up and run for awhile and then randomly shutdown, etc., or does if not start at all now?

Besides the fan in the power supply and the CPU fan, how many fans do you have installed in your computer?  Where are they?  Which direction are they moving air?

Did you make any hardware changes (excluding the power supply) before this started happening?  Add a video card or other new components?  Have you ever removed the CPU fan and heatsink?  

Do have any way now of getting temperature readings for the CPU?  If not, I suggest you download SpeedFan and install it and see what info it will produce for that computer.

Yes it still starts up and runs and randomly shutsdown, PSU fan is the only fan no room for anymore, hadn't made any hardware changes besides PSU, I already have speed fan and the only info it gives me is some basic HDD and memory info.