Hi all
Help !!
When i switch on my computer tower the monitor light goes from green to yellow and i have no display.
I have checked the leads and also proved that this monitor is ok by trying it on another pc.
I upgraded the RAM in this pc from 1 to 2GB 2 days ago and it was working fine (and quicker) until today.
My pc is a Fujitsu Scaleo Pi 1522 with Windows vista home premium.
Any ideas please what i can do ?
Regards
Colin

I have moved your post to the Hardware Help forum. Hardware Discussions are general discussions about hardware, not specific problems.

Since you just added new hardware, and now it does not work, it could be you have added more hardware than your power supply can handle. Please tell us about your computer. Start by removing the new RAM and see if it fixes itself. If still bad, I would look at testing your PSU. Here's my canned text on that:

To properly and conclusively test a power supply unit (PSU), it must be tested under various realistic "loads" then analyzed for excessive ripple and other anomalies. This is done by a qualified technician using an oscilloscope or power analyzer - sophisticated (and expensive) electronic test equipment requiring special training to operate, and a basic knowledge of electronics theory to understand the results. Therefore, conclusively testing a power supply is done in properly equipped electronic repair facilities.

Fortunately, there are other options that are almost as good. I keep a FrozenCPU Ultimate PSU Tester in my tool bag when I am "in the field" and don't have a good spare power supply to swap in. While not a certain test, they are better than nothing. The advantage of this model is that it has an LCD readout of the voltage. With an actual voltage readout, you have a better chance of detecting a "failing" PSU, or one barely within specified ATX Form Factor Standard tolerances. Lesser models use LEDs to indicate the voltage is just within some "range". These are less informative, considerably cheaper, but still useful for detecting PSUs that have already "failed". Newegg has several testers to choose from. All these testers contain a "dummy load" to fool the PSU into thinking it is connected to a motherboard, and therefore allows the PSU to power on, if able, without being attached to a motherboard - great for testing fans, but again, it is not a true load or suitable for conclusive testing.

As mentioned, swapping in a known good supply is a tried and trued method of troubleshooting used for centuries, even by pros. Remove the "suspect" part and replace with a "known good" part and see if the problem goes away.

I do not recommend using a multimeter to test power supplies. To do it properly, that is, under a realistic load, the voltages on all the pins must be measured while the PSU is attached to the motherboard and the computer powered on. This requires poking (with some considerable force) two hard and sharp, highly conductive meter probes into the main power connector, deep in the heart of the computer. One tiny slip can destroy the motherboard, and everything plugged into it. It is not worth the risk considering most multimeters, like plug-in testers, do not measure, or reveal any unwanted and potentially disruptive AC components to the DC voltages.

And remember, anything that plugs into the wall can kill. Do not open the power supply's case unless you are a qualified electronics technician. There are NO user serviceable parts inside a power supply.

Thks for quick response.
I will remove the RAM and restart my PC.
However i forgot to mention that this problem has occured previously to now but seemed to correct it self if i powered off at the mains,also the display would intermitently go black when changing users !
My PC is Intel core 2 cpu 4300 @1.80 Ghz
Graphics card NVIDIA GeForce 7300 SE/7200GS

Regards

Hi all
Removing the RAM did not make any difference.
Is there anything else anyone can suggest before i "call in a man" to test the CPU ?
Could it be the graphics card ?
Being pressured by the family to fix it !!!
Hope somebody can help
Regards
Col

I would still want to know the power supply was providing good, clean power.

Hi all
What i did notice when i checked inside the pc the other day was the amount of dust that was present.
So gave it a good "air blow" and hey presto it is working fine !!
This could have been the cause.
Hope this helps someone.

Regards

As noted in my sig, heat is the bane of all electronics. I generally recommend a visual inspection once a month, then clean, and/or adjust inspection interval as necessary.

This could have been your problem, but generally it takes some time for heat to build up to cause problems (unless a critical fan has seized). Your opening post led me to believe the problem was happening with a system that had been turned off, and was cooled. I hope your problem is resolved, and a clean machine is important anyway, but, if this problem happened after the system had fully cooled down, it probably was not caused by the dust, and may raise its head again.