Bad PSU?

[cupajava]

So I have my HTPC setup in Silverstone Lascala 13 case and it's been on most of the time and giving me minor headaches once in a while with BSOD. One day, I turned it on a and all that was there was a black screen with the cursor appearing after the WINDOWS logo came on. I was running XP at the time so I thought the OS got corrupted cause rebooting would have the same result. Power led is on but hard drive stops reading after Windows logo. Fans are all working.

So I decide to upgrade to Vista. After that all seemed well. Left it on like the old pc and forgot about it. Came back suddenly just had a black screen and no response or cursor showing. Rebooting won't even take me to the bios. If I remove the top of the case, pc starts no problem. I haven't left the case off for too long but I'm wondering if there is a short. Is that indicative of a bad PSU? Now, this may also be a bad setting in Vista and never coming out of hibernate mode as well. Just odd I'm gettting similar problem with both OS. Mayby bad mobo? Like I said, all appears fine. I put the top of the case on and everything is still good. Come back an hour later and black screen but power led on and all fans on. HD is not responsive. If I take the top of case off and blow out the inside. Everything appears normal. CPU fan is running by the way (athlon X2 3800).

New mobo or psu?

 

[mpilchfamily]

Since it works fine with the sover off i'd say its a heat issue. So first thing you need to do is give it a good cleaning and make sure dust isn't clogging the coolers. If that doesn't help much or the system is already clean then find a way to add more cooling. You may also want to check the CPU cooler to see if its mounted correctly or needs to be remounted.

 

[cupajava]

Thanks MP. After some further analysis, I believe the problem is the pc is going into sleep mode instead of the screensaver coming on and the pc can't come out of sleep mode unless I disconnect the power supply before restarting. Anyone know how to change Vista so sleep mode is not enabled?