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From: MN on 11 Jun 2010 15:43 Paul, I took the mobo out of the case and placed it on cardboard. I applied AC power and was able to get the case power LED to glow in response to pressing the case power button. I still do not get (1) any beeps from the piezo-electric beeper (I can see the piezo on the mobo), (2) no movement of the CPU-mounted fan (3-wire connection to mobo for speed control), and (3) any output on the monitor. All of the above were true before and after I removed all connections to the mobo, other than the 20-pin and 4-pin power connectors as well as removal of the DDR2 memory sticks. The logical conclusion, as indicated by items (1) thru (3) above is that the CPU is NOT running -- since EACH of those items requires the CPU to execute BIOS code. Furthermore, I cleared the CMOS data by applying the jumper as per the manual's instructions, and also measured the CMOS battery voltage to be 3 volts. (I used a wrist strap connected to ground when working on the mobo.) The processor I installed was an new Intel socket M Core-Duo processor T2450 (SLA4M). It is a PGA package device. The mobo supports a broad range of socket-M PGA CPUs, both single and dual core including a CeleronM. I don't think I have am using an incompatible CPU. Thus the question is: WHY ISN'T THE CPU RUNNING AND EXECUTING BIOS CODE? Observation: I do sense a very slight warmth under the CPU when the power is ON. All I definitely know is that the power supply provides the correct voltages to the mobo and the mobo's hardwired power-button & associate LED logic functions. Could there be connection problems between the mounted CPU and the mobo socket? I guess I can remove and reinstall the CPU and heat-sink/fan to find out. Any other suggestions? -Marty "Paul" <nospam(a)needed.com> wrote in message news:hustaj$s5k$1(a)news.eternal-september.org... > MN wrote: > >> >> *** I will take the mobo out of the case. But if it is not grounded to >> the case by the mounting screw/standoffs, won't this be a problem? >> > > Ground is provided in three ways on a motherboard. > > 1) The black wires on the main ATX power supply cable are ground. > > 2) Where the conducting motherboard tray standoffs touch the > bottom of the motherboard, on the plated_thru holes, is ground. > The purpose of the ground, may be for RF emissions control, rather > than DC current conduction. > > 3) The I/O plate inserted in the computer case, has shiny springy > metal contacts. They press against the I/O stack shiny metal body. > That causes chassis ground to electrically touch and contact the > stack. That is for ESD discharge and RF EMI control as well. > > If you place a motherboard on a cardboard covered telephone book, > you lose (2) and (3), but (1) has you more than covered. The > DC return currents continue to flow over the black wires and > all is good. > > I've built and tested two computers, sitting on telephone books, > and they worked fine. No instability, no complaints. Once tested, > I disassembled and placed the components into the case as normal, > knowing all the hardware was working. > > Paul
From: Paul on 11 Jun 2010 16:09 MN wrote: > Paul, > I took the mobo out of the case and placed it on cardboard. I applied AC > power and was able to get the case power LED to glow in response to pressing > the case power button. I still do not get (1) any beeps from the > piezo-electric beeper (I can see the piezo on the mobo), (2) no movement of > the CPU-mounted fan (3-wire connection to mobo for speed control), and (3) > any output on the monitor. All of the above were true before and after I > removed all connections to the mobo, other than the 20-pin and 4-pin power > connectors as well as removal of the DDR2 memory sticks. The logical > conclusion, as indicated by items (1) thru (3) above is that the CPU is NOT > running -- since EACH of those items requires the CPU to execute BIOS code. > Furthermore, I cleared the CMOS data by applying the jumper as per the > manual's instructions, and also measured the CMOS battery voltage to be 3 > volts. (I used a wrist strap connected to ground when working on the mobo.) > > The processor I installed was an new Intel socket M Core-Duo processor T2450 > (SLA4M). It is a PGA package device. The mobo supports a broad range of > socket-M PGA CPUs, both single and dual core including a CeleronM. I don't > think I have am using an incompatible CPU. Thus the question is: WHY ISN'T > THE CPU RUNNING AND EXECUTING BIOS CODE? Observation: I do sense a very > slight warmth under the CPU when the power is ON. All I definitely know is > that the power supply provides the correct voltages to the mobo and the > mobo's hardwired power-button & associate LED logic functions. > > Could there be connection problems between the mounted CPU and the mobo > socket? I guess I can remove and reinstall the CPU and heat-sink/fan to find > out. Any other suggestions? > > -Marty > CPU-World says that processor is socket M and they provide this page with information on the socket. http://www.cpu-world.com/Sockets/Socket%20M%20(mPGA478MT).html "Instead, the socket has a special actuator that needs to be turned by about half-turn to lock or release the processor." That is a zero insertion force (ZIF) socket, where instead of a lever to work the contacts, a screw closes the contacts. You can see the lock screw at one end of each socket picture. Paul
From: MN on 11 Jun 2010 17:35 Paul, Thanx again. I do have that info and originally used it (together with the T2450 Intel data sheet) in determining the appropriate chip to purchase. When I installed the CPU (which could only be inserted one way because of the blocked pin-hole in the mobo CPU socket), I did tighten the ZIF screw to clamp the pins tight. Then, (1) I placed the backplate for the heatsink/fan assy on the underside of the mobo, and (2) screwed the heatsink/fan assy (on the top side of the mobo) threw the mobo holes into the mated threads of the backplate. In adjusting the 4 spring-loaded corner-screws, there was no stop provided, so one could conceivably overtighten the heatsink/fan assy onto the CPU. (The ZIF lever, used on other CPUs did not present that situation and was a lot easier than adjusting 4 screws while holding the heatsink/fan assy and backplate at the same time). (Comment: I wondered if the metallic surface of the backplate might short some metallic traces on the underside of the mobo.) I am going to remove the heatsink/fan assy and see if the CPU looks damaged due to overtightening. Assuming the CPU does not appear damaged, and appears to be tight in its socket, I plan to power up the mobo, temporarily, without the heatsink/fan assy installed. I should hear beeping if the CPU is running BIOS code. If not, I may remove the CPU, reinstall it, and try again. I really don't like removing the thermal contact between the heatsink and CPU surface; I don't have any thermal paste to apply when I re-install the heatsink/fan assy. ========================================================== > MN wrote: >> ......... >> >> Could there be connection problems between the mounted CPU and the mobo >> socket? I guess I can remove and reinstall the CPU and heat-sink/fan to >> find out. Any other suggestions? >> >> -Marty >> > Paul Replied: > > CPU-World says that processor is socket M and they provide this page with > information on the socket. > > http://www.cpu-world.com/Sockets/Socket%20M%20(mPGA478MT).html > > "Instead, the socket has a special actuator that needs to be turned > by about half-turn to lock or release the processor." > > That is a zero insertion force (ZIF) socket, where instead of a lever to > work the contacts, a screw closes the contacts. You can see the lock screw > at one end of each socket picture. > > Paul
From: Paul on 11 Jun 2010 22:06 MN wrote: > Paul, > Thanx again. I do have that info and originally used it (together with > the T2450 Intel data sheet) in determining the appropriate chip to purchase. > > When I installed the CPU (which could only be inserted one way because > of the blocked pin-hole in the mobo CPU socket), I did tighten the ZIF screw > to clamp the pins tight. Then, (1) I placed the backplate for the > heatsink/fan assy on the underside of the mobo, and (2) screwed the > heatsink/fan assy (on the top side of the mobo) threw the mobo holes into > the mated threads of the backplate. In adjusting the 4 spring-loaded > corner-screws, there was no stop provided, so one could conceivably > overtighten the heatsink/fan assy onto the CPU. (The ZIF lever, used on > other CPUs did not present that situation and was a lot easier than > adjusting 4 screws while holding the heatsink/fan assy and backplate at the > same time). (Comment: I wondered if the metallic surface of the backplate > might short some metallic traces on the underside of the mobo.) > > I am going to remove the heatsink/fan assy and see if the CPU looks > damaged due to overtightening. Assuming the CPU does not appear damaged, and > appears to be tight in its socket, I plan to power up the mobo, temporarily, > without the heatsink/fan assy installed. I should hear beeping if the CPU > is running BIOS code. If not, I may remove the CPU, reinstall it, and try > again. I really don't like removing the thermal contact between the heatsink > and CPU surface; I don't have any thermal paste to apply when I re-install > the heatsink/fan assy. > Visually examine the backplate. Some of them have insulation to prevent accidental contact with components. When the motherboard designer is laying out the board, there are usually "keepout zones" defined to the mechanical features, and that is how backplate/heatsink makers are supposed to stay out of trouble. You'll see white lines on the motherboard, showing the profile of the backplate location or where the heatsink is expected to go on the top of the motherboard. Those white lines are intended to show the keepout zones defined in the layout tool. With regard to thermal paste, you should always have at least one tube on hand. I have a $5 tube that I've been using for years. A little bit of it, goes a long way. If the current material is scratched up, distorted or it is preventing the heatsink from sitting flat, then clean off the existing material and apply some paste. You never want the paste to get on components (tiny resistors or capacitors), or get down into the socket pin or contact area. Applying a half-grain of paste, squashing the heatsink into it, should show a "circle" of paste, and the size of that circle will help you judge how big a dab is needed to do the whole thing. Cleaning kit, if you need it. http://www.newegg.com/Product/Product.aspx?Item=N82E16835100010 Ceramique http://www.newegg.com/Product/Product.aspx?Item=N82E16835100009 (You can download the MSDS, to see what they're made from, like boron nitride) http://www.arcticsilver.com/PDF/thermcom/CMQ_MSDS_3.pdf Sometimes, you can buy replacement materials, certified as being acceptable to AMD or Intel, but most of us just use paste to do the job. You only need to re-apply paste, if you notice the monitored CPU temperature getting out of hand, in a few years time. Paul
From: MN on 11 Jun 2010 23:45
Paul, I did remove the heatsink/fan assy and checked the CPU for damage, etc; it appeared OK. I then removed the CPU and reinserted it, using the ZIP locking screw. I then replaced one of the 2 Gig DDR2 memory sticks, and applied power and presssed the case power button. For the first time, I got a SINGLE beep and saw the BIOS screen on the monitor. Unfortunately, it shutdown after a few seconds. I repeated pressing the the case power button with the same results: shutdown after a few seconds. Pressing DEL to enter BIOS setup did no good; it shutdown too quickly. Since the processor was getting quite warm, I stopped powering-up the mobo. Later, I replaced the heatsink/fan assy and backplate. Then I repowered up the mobo. It would not beep or display the BIOS screen on the monitor. I removed the backplate (but keeping the the heatsink/fan assy on top of the CPU) and powered-up the mobo; it again worked for a few seconds. After doing this a few times, I noticed that the the heatsink/fan assy was getting quite hot. It should be noted the fan NEVER rotated! The quick shutdown probably occurred because the BIOS was set to shutdown on specific detected error(s). (Shutdown Temperature exceeded, no drives connected, etc.) Although, I thought of spray painting the backplate and using it again, I am considering getting a heatsink/fan assy that provides better cooling. (The CPU got hot pretty quickly although it was not doing very much.). Thanx for mentioning the Arctic Silver products. I will definitely need them, now. Since I will be ordering the Arctic Silver products, I might as well try to find and then buy a more efficient heatsink/fan assy. Marty ============================================================== MN wrote: >> >> I am going to remove the heatsink/fan assy and see if the CPU looks >> damaged due to overtightening. Assuming the CPU does not appear damaged, >> and appears to be tight in its socket, I plan to power up the mobo, >> temporarily, without the heatsink/fan assy installed. I should hear >> beeping if the CPU is running BIOS code. If not, I may remove the CPU, >> reinstall it, and try again. I really don't like removing the thermal >> contact between the heatsink and CPU surface; I don't have any thermal >> paste to apply when I re-install the heatsink/fan assy. >> Paul replied > Visually examine the backplate. Some of them have insulation to prevent > accidental contact with components. When the motherboard designer is > laying out the board, there are usually "keepout zones" defined to the > mechanical features, and that is how backplate/heatsink makers are > supposed to stay out of trouble. You'll see white lines on the > motherboard, > showing the profile of the backplate location or where the heatsink is > expected > to go on the top of the motherboard. Those white lines are intended to > show > the keepout zones defined in the layout tool. > > With regard to thermal paste, you should always have at least one tube > on hand. I have a $5 tube that I've been using for years. A little > bit of it, goes a long way. If the current material is scratched up, > distorted or it is preventing the heatsink from sitting flat, then > clean off the existing material and apply some paste. You never want > the paste to get on components (tiny resistors or capacitors), or > get down into the socket pin or contact area. Applying a half-grain > of paste, squashing the heatsink into it, should show a "circle" of > paste, and the size of that circle will help you judge how big a dab > is needed to do the whole thing. > > Cleaning kit, if you need it. > > http://www.newegg.com/Product/Product.aspx?Item=N82E16835100010 > > Ceramique > > http://www.newegg.com/Product/Product.aspx?Item=N82E16835100009 > > (You can download the MSDS, to see what they're made from, like boron > nitride) > > http://www.arcticsilver.com/PDF/thermcom/CMQ_MSDS_3.pdf > > Sometimes, you can buy replacement materials, certified as being > acceptable > to AMD or Intel, but most of us just use paste to do the job. You only > need to re-apply paste, if you notice the monitored CPU temperature > getting out of hand, in a few years time. > > Paul |