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Honeywell st499a/st699b central heating microelectronic time controller. it's got 2 switches 1 for heating and 1 for hot water. when i turn on hot water only heating works as well and vice versa. how can i sort that out. tried calling honeywell who are useless and have nobody on the phone. thanks aleks

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Computer keeps overheating

Your power supply has a theoretical Maximum output of 700 watts, but the problem is that the hotter it gets the lower that number becomes... It's obvious your power supply can't handle the power draw or the heat from the Graphics card when taxing it by playing games... Two things you should do:

1. Make sure you have more than just your power supply venting hot air out of your case... Adding a fan or 2 will help take some of the cooling stress off the power supply.

2. Buy a better power supply... is a place I get most of my PSU's. Read their ratings and compare specs. You will notice on that site that your particular model is not rated very high.

May 10, 2012 | System Power Supplies

1 Answer

No power

Check the small glass fuse soldered to the board inside. If you don't know what you're doing, do NOT open this unit. IF it is a "SWITCHING" supply, (different than a "SWITCHABLE" supply), there could be high voltage capacitors still charged that can give you a nasty zap. If there's a shop you trust and it is just a fuse, it shouldn't cost much to fix. One time I saw a unit that didn't work that turned out to be the 110 / 220 volt switch was slid 1/2 way between the 2 positions.
I'm sure this isn't much but I hope it helps.

Feb 02, 2011 | Epson Power Supply 110/200 VAC Switchable...

2 Answers

How to power up a compaq 243890-001 power supply without the the motherboard? Its not green to ground

Remove Power Supply
1 . Shut down your computer and unplug the power cord and all cables connected to the system.

2 . Open the computer case and disconnect all power connectors from the motherboard, drives, cards and fans.

3 . Remove the four screws that secure the power supply to the case. These screws are located on the back of the computer case, at each corner of the power supply.

Wire and Start Power Supply
1 . Switch the power supply to the "Off" (sometimes "O") setting.

2 . Insert the end of one wire from a single pole, single throw (SPST) switch into the green wire of the ATX power connector (the largest power supply connector).

3 . Insert the end of the other wire from the SPST switch into the black wire of the ATX power connector. If your power supply has two black wires, connect the SPST to the black wire directly beside the green wire.

4 . Wrap electrical tape around the ATX power connector and wires from the SPST switch to hold them in place. Make sure there is no exposed copper or silver wire from the SPST switch wires.

5 . Turn the SPST switch to the "Off" position, if not already set. Plug the power supply into the wall outlet and switch it to the "On" (sometimes "I")setting.

6 . Connect any other computer components that you wish to operate without the motherboard, such as fans, drives or cards. Turn the SPST to the "On" setting to activate the power supply.

Hope the above information will be helpful to you.

Dec 01, 2010 | Compaq (243890-001) 250-Watt Power Supply

1 Answer

One of the Power Supplies is dead and over heating causing it to beep

Fist clean your computer of dust using a fine air blower from a compressor specifically around your CPU central processing unit making sure there is no moisture in the air line
as dust will cause a lot of static which will make a computer overheat and cause lots of problems
then test your power supply unit PSU or replace it
the beeps are post during post the very first work is done by the ram,all the memory in the ram is first transferred to the hard disk,and remains active untill turned off.
make sure that RAM is securely seated
try replacing all the leads that attach to your hard drive including electrical extensions + IDE,SATA the ones that attach from your motherboard to hard drive
make sure all leads that are attached to your drives dvd\cd 3 1/2 inch floppy have secure connections and are not faulty or just replace them they are probably old and faulty ?
heres a tip

then click start?run type?cmd then type?chkdsk/f which will automatically fix any corrupt files on your hard drive then defragment your hard drive
you have to keep?a computer very clean & free of dust ?and? give it regular?maintanance
good luck with this

Nov 23, 2010 | I-Star TC-400R8 PS/2 Redundant 400W Power...

1 Answer

Enermax EG495P-VE (Off warranty) will run for 1 sec to 1 min and then shut down. No volts to 12/5/3.3. For the brief time that it stays on it supplies the correct volts under load. Is there a overload...

It's probably an accumulation of lint, dust, pollen, and anything else in the air over time, if you're lucky. This isn't the easiest of things to do, but you will have to use a small brush for a lot of clingy stuff, to compressed air for most cases. It could be a slight short in the fan motors, or a bad electrical connection or connector that's causing the current to rise and trip a thermister, or other heat sensing device. I would take it apart and see what I could see. Most of the time it's something simple, never know till you look.
One thing...if you do find an overload switch or circuit, figure out the problem that's making it overload. It's probably not the switch that's bad, but something else. Good luck!

Mar 27, 2010 | Enermax EG495P-SFMA24P Very Quiet...

1 Answer

Power sypply overheat

Check that the power supply fan is operating. If not, take it back under warranty.

Feb 17, 2010 | Coolmax VL-600B 600W ATX 12V V2.3 Power...

1 Answer

Hp pavilion a450n turns on but wont open past countdown

probably itz either minor case of software corruption/improper ground/cpu fan..
or major case of faulty or defective main board/ram/daughter or addon card(s)..

..plz do check the following as in order:..
the Hardware part:..
1)see if the ram(s) is loose/ clean/remove carbon & or oxide formed on the teeth with an eraser n resit it..or replace with a standby n see..

2) 4) a) see if ur hdd is noisy or emitting any 'ticking' noise (like 'tuk tuk' or 'kirr kirr')..
b) or if the system is not supporting either the newly installed device or itz software/driver /firmware
if so, u need either a fresh os installation or ur hdd is likely to b replaced..

3)remove/clean dust neatly..dust is non-uniform in nature n may cause jam/short circuitry/excess resistance n many more..resulting an increase in heat..

4) open the CPU Heat-Sink with fan out of the socket..put some "Heat Sink Compound" (available in local electronics chip level spare market) between the cpu/processor and the CPU Heat Sink *** fan..resit/fit it tightly in position..

5) on main/mother board..see with a debug card for mb error..may b short..look for defective capacitors(esp above1000mfd)/mosfets..go through the mb's south bridge n the circuit lie around atx connector..the crystal clock generator (if cpu isn't heating up)..

6) [in case of desktop] the smps itself may b defective/faulty..check the outputs of smps viz. 0v (black~ground); +12v (yellow); +5v (red, green~ps-on, violet~pg & grey~sb); -12v (blue); -5v(white); +3.3v(orange)..the 'oscillator and error amplifier ic', or pwm switching regulator circuit..look for defective protector-transformer/resistance(esp 4.7k)/mosfet..
check the battery [both main power & cmos], in case of laptops..

the Software part:..
1) hv a licensed and UPDATED antivirus installed (i prefer avg/kaspersky, remember, without updation a full version antivirus is useless)..

2) download, install n run microsoft kb890830..

3) download n run Startup Control Panel..'remove all the unnecessary startup items from here..(if u can't find what to remove, post me/us in ur comment with all the items listed in each n every tabs herein)..

4) remove all unnecessary software from add/remove programs..

5) download, install n run 'Advanced System Care Pro'..

6)disable the following:..
a) 'Automatically Restart' right click on my computer->properties->advanced->startup n recovery->(uncheck on the) Automatically Restart;
b)'Error Reporting' right click on my computer->properties->advanced->error reporting->disable error reporting->(uncheck on the) 'but notify me when critical error occur'..

7) Increase the size of Virtual Memory, Initial: 1440; Maximum: 2880

if u r bot a professional, always better to seek advise from ur system admin/vendor....

Nov 15, 2009 | HP System Power Supplies

1 Answer

Main power cord overloaded

Generally they do but they do not have a sensor in the cable. The 120v cord will overheat if you are drawing too much wattage through it. If you are using a gaming system or server with high wattage powersupply and still using a standard cord(many people re-use the one already there when they swap out machines) it may simply be too thin to carry the load. Also if the cord developed a pinch in it there could be a narrow point causing the hot spot.

Try finding a heavier cord, generally something bigger than 16ga wires and monitor the cord for a few minutes while the machine fires back up. If you're not familiar with gauges, measure the diameter of the current cord in mm and fin one at least 2-3mm thicker, this should allow aprox 2 times the wattage to pass without excess heat.

Hope this helps


May 03, 2009 | System Power Supplies

1 Answer

Problem with controller time display no working properly

is there a model number I might be able to help you

Nov 04, 2008 | System Power Supplies

1 Answer

HP 0950-2060

go online and do a search for a computer power supplys as I do when I need one and find all I need at a touch of a button for less then 30 bucks most of the time + shipping. Good luck

Mar 21, 2006 | HP/COMPAQ - 0950-2060 (09502060) Power...

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