My motherboard have power but no display on screen

Check out power supply , common source of problem. If that is ok then you may have a bad peripheral or bad motherboard.

Maybe your screen is kaput - hook up an external monitor to see if that works.

Main processor [CPU] do not detect all the other peripherals. Any voltage loss can cause this. Your PCs motherboard need to be checked. It will be best to contact the authorized service centre for Sony; in this case. This is not a user detectable fault.
http://electronicshelponline.blogspot.com/

OK, I use GX280s as home servers and ran into a similar problem with one of them...

The problem may be serious and not worth fixing (motherboard).

Turn power on
Fan(s) come on full power, sounds like a jet engine, or eventually gets that loud.

See if you power light has gone amber.

You get nothing on the screen, no Dell splash screen/post, nothing.

This is what I posted a while back concerning the above. Obviously I cannot bee 100% certain as I do not have your box in front of me. This a known issue.

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See if the power light goes amber after power up. I had (have - still siting in my basement) one that did same. Power up, fans go full blast . Power light goes and stays amber. This is USUALLY caused by bad capacitors on the mother board. Known GX280 problem going back. If you look on the motherboard, the capacitors should have flat tops and not leaking. If the are rounded or leaking, the MB has probably gone bad. Bottom line this is usually a defective motherboard. Mine was a bad caps issue, you issue could be different, but it does sound like the motherboard.

You can google "gx280 solid amber light loud fan" and see the issues. Here is one link.

http://community.spiceworks.com/topic/111476-gx280-solid-amber-light-and-loud-fan

I just replaced one of my old 280s with a dual core Dell Precision 390 workstation for about $118, and that included shipping, off of ebay.

Check around the motherboard for capacitors with bulging tops.
Type bulging capacitors in google images to see examples.
It's a very common fault, and especially in power supplies and around the processor or power section of a motherboard.

MY DEAR FRIEND


CAN you tell me the what is the display problem

OK

Hi,
I would check your power supply with a meter to see if that's the problem. If it checks out ok then it's probably the mobo. In rare instances when a power supply goes it takes the mobo with it.
Best of luck...Hank

if your processor does not heat up it's probably dead.. try running it without the fan and see if the heat sink still doesn't heat up

check first your RAM memory and your video card. if ok all. try another ATX power supply.

Immediately change your motherboard.

motherboard problem motherboard can't display when switch on, the cpu fan faster no beeping . I had change power supply, but same.Check the keyboard LED,Not flash.I had remove the ram but can't hear beep. PC speaker ok conferm. Monitor display tested monitor its ok . But no comming display. Can you help me? How i can solve this problem?