vanilla ice
1 MW
ISA? VLB? PCI? AGP? PCIe? I just send a load to the recyclers but I might have something left I could post you. Need a 5.25" floppy drive BTW?? hehe.
The 12 Volt + LVC + HVC + Balancer + PIC... Thread
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safe
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It was an ATI 64MB Radeon 7500 PCI card.vanilla ice said:
I've got an old Dell P780 Monitor.
If you've got anything that would work for me I could PayPal you enough for shipping. I'm not looking for much and this sort of thing is more or less free these days, but it's a matter of finding it. I spent the day in the garage working on bikes and the last thing I want to do is look around for old computer stuff. And buying new stuff makes no sense given my clunky old computer.
What I really need is a new computer... or at least a used one that is less old. Seems like electrical equipment fails faster here in the midwest because we have lot's of electrical storms. Even with a surge protector (unless you replace them every year) they wear out and give less and less protection.
Of course, realistically this card was used continuously for about five years, so it's not that unexpected...
Ypedal
100 TW
Got any pawn shops locally ? they would likely pay you to take away old PCI cards..
safe
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GeForce FX5200 Video Graphics Card - $25
I found a guy in my general neighborhood on Craigslist that has one of these for $25. If I can get the guy to arrive at my door to deliver it that's about as good as I can expect. At the big chain stores they always want $100 for everything no matter what you want.
I've got AGP and PCI slots. If anyone wants to sell me something better for less speak now or it's too late...
I found a guy in my general neighborhood on Craigslist that has one of these for $25. If I can get the guy to arrive at my door to deliver it that's about as good as I can expect. At the big chain stores they always want $100 for everything no matter what you want.
I've got AGP and PCI slots. If anyone wants to sell me something better for less speak now or it's too late...
vanilla ice
1 MW
I found an AGP s3 "savage IV" but you're on your own for drivers and I'm not sure it even works, but zero bucks and its yours. I found some old bnc co-ax ISA NICs too... man you forget how nice you got it!
TylerDurden
100 GW
Intel Offers Classmate PC in Developed Countries
Sumner Lemon, IDG News Service
Thursday, March 20, 2008 7:10 AM PDT
Intel's Classmate PC isn't just for students in emerging markets anymore. The low-cost laptop will be made available to companies that want to sell it to consumers in developed countries, an Intel executive said Wednesday.
"During the last quarter, we have seen tremendous interest in the Classmate PC from customers outside education," said Tom Rampone, an Intel vice president and general manager of the company's Channel Platforms Group, adding that Asustek Computer's Eee PC helped stoke wider interest in low-cost laptops.
Originally designed for schools in emerging markets where computer access is rare, the Classmate PC uses a low-power version of the Celeron M processor and a 7-inch screen. Intel is working on a second version of the Classmate PC, earlier revealing plans to use its upcoming Atom processor in the new laptop. Detailed specifications of the device have yet to be revealed.
Intel sees the Classmate PC as just one of a range of low-cost laptops now being developed that the chip maker and others call "netbooks." These laptops are generally expected to cost between US$250 and $300, depending on how they are configured, when they hit the market later this year.
The move to expand the availability of Classmate PC to PC vendors in developed markets follows a push to make the Classmate PC more widely available to consumers in emerging markets. For example, HCL Infosystems of India announced a laptop, called MiLeap X, earlier this year that is based on the Classmate PC design but marketed as a low-cost computer for consumers and businessmen instead of students.
The second version of the Classmate PC will be available to PC vendors in a range of configurations, but will retain the same basic design when sold by different vendors, Rampone said. In addition to versions for consumers, running either Linux or Windows, the laptop will be available in configurations, complete with educational software, aimed at schools in developed countries, he said.
http://www.pcworld.com/article/id,143627-page,1/article.html
Sumner Lemon, IDG News Service
Thursday, March 20, 2008 7:10 AM PDT
Intel's Classmate PC isn't just for students in emerging markets anymore. The low-cost laptop will be made available to companies that want to sell it to consumers in developed countries, an Intel executive said Wednesday.
"During the last quarter, we have seen tremendous interest in the Classmate PC from customers outside education," said Tom Rampone, an Intel vice president and general manager of the company's Channel Platforms Group, adding that Asustek Computer's Eee PC helped stoke wider interest in low-cost laptops.
Originally designed for schools in emerging markets where computer access is rare, the Classmate PC uses a low-power version of the Celeron M processor and a 7-inch screen. Intel is working on a second version of the Classmate PC, earlier revealing plans to use its upcoming Atom processor in the new laptop. Detailed specifications of the device have yet to be revealed.
Intel sees the Classmate PC as just one of a range of low-cost laptops now being developed that the chip maker and others call "netbooks." These laptops are generally expected to cost between US$250 and $300, depending on how they are configured, when they hit the market later this year.
The move to expand the availability of Classmate PC to PC vendors in developed markets follows a push to make the Classmate PC more widely available to consumers in emerging markets. For example, HCL Infosystems of India announced a laptop, called MiLeap X, earlier this year that is based on the Classmate PC design but marketed as a low-cost computer for consumers and businessmen instead of students.
The second version of the Classmate PC will be available to PC vendors in a range of configurations, but will retain the same basic design when sold by different vendors, Rampone said. In addition to versions for consumers, running either Linux or Windows, the laptop will be available in configurations, complete with educational software, aimed at schools in developed countries, he said.
http://www.pcworld.com/article/id,143627-page,1/article.html
safe
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I know, I know.... I'll get around to it. :?
Look's like I'm able to pull 1024 x 768 if I drop my color depth a little. So once I got all the right drivers installed and fiddled with it awhile it's okay.
I've been welding, cutting and grinding so I haven't had as much time to focus on this. Free is always better than spending money when you don't have to...
Look's like I'm able to pull 1024 x 768 if I drop my color depth a little. So once I got all the right drivers installed and fiddled with it awhile it's okay.
I've been welding, cutting and grinding so I haven't had as much time to focus on this. Free is always better than spending money when you don't have to...
safe
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Basis For A Successful Circuit
I'm going to have to make up the full circuit for the 12 volt format in the simulation program, but this is the core component that solves (or appears to solve) the Power MOSFET leakage problem. Basically by inserting a resistor in the "Off State" (wire) bypass portion of the circuit you inhibit the backwards current leakage. As long as the "On State" (power) MOSFET is open the fact that the "Off State" (wire) is closed is no longer a problem. You really only need to protect for the voltage difference of the cell itself, so you only need a resistor that can inhibit the cell voltage... just a few volts worth.
I'm going to have to make up the full circuit for the 12 volt format in the simulation program, but this is the core component that solves (or appears to solve) the Power MOSFET leakage problem. Basically by inserting a resistor in the "Off State" (wire) bypass portion of the circuit you inhibit the backwards current leakage. As long as the "On State" (power) MOSFET is open the fact that the "Off State" (wire) is closed is no longer a problem. You really only need to protect for the voltage difference of the cell itself, so you only need a resistor that can inhibit the cell voltage... just a few volts worth.
safe
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Diode Based 12 Volt Circuit
Still not sure how to get the PIC to be able to trigger the gate voltage at a high enough voltage (ideally you need to find MOSFET's that open with only 2.5 volts... which I know is possible, but then whether they can handle the amps is uncertain... a Catch-22 quite possibly)
In the simulation program this works perfectly... which tends to make me worried... it's just too simple to be correct... :lol:
Still not sure how to get the PIC to be able to trigger the gate voltage at a high enough voltage (ideally you need to find MOSFET's that open with only 2.5 volts... which I know is possible, but then whether they can handle the amps is uncertain... a Catch-22 quite possibly)
In the simulation program this works perfectly... which tends to make me worried... it's just too simple to be correct... :lol:
safe
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Update
There have been some advances that took place on another thread and now the "official" concept for the base circuit looks like this:
...it's been run through a simulation in both forward power and reverse charging conditions and everything looks right. Compared to the original design the MOSFET's are inverted, so the power direction has forward oriented MOSFET's and the ByPass path has reverse oriented MOSFET's.
The next step will be to go to a more economical 12 volt design that exploits the PIC to coordinate everything...
There have been some advances that took place on another thread and now the "official" concept for the base circuit looks like this:
...it's been run through a simulation in both forward power and reverse charging conditions and everything looks right. Compared to the original design the MOSFET's are inverted, so the power direction has forward oriented MOSFET's and the ByPass path has reverse oriented MOSFET's.
The next step will be to go to a more economical 12 volt design that exploits the PIC to coordinate everything...
safe
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12 Volt MOSFET Math
The maximum voltage that can be present across a four cell (12 volt) battery is:
4.25 volts * 4 = 17 volts.
The maximum power dissipation for that given a 50 amp current limit is:
50 amps * 17 volts = 850 watts.
Assuming we use four MOSFET's in the forward direction and four more in the bypass direction:
850 watts / 4 = 215 watts
So I need to find a low priced MOSFET that has low resistance and can handle about 250 watts and about 15 amps of current. Either that or some other MOSFET that can be used in some other configuration.
The maximum voltage that can be present across a four cell (12 volt) battery is:
4.25 volts * 4 = 17 volts.
The maximum power dissipation for that given a 50 amp current limit is:
50 amps * 17 volts = 850 watts.
Assuming we use four MOSFET's in the forward direction and four more in the bypass direction:
850 watts / 4 = 215 watts
So I need to find a low priced MOSFET that has low resistance and can handle about 250 watts and about 15 amps of current. Either that or some other MOSFET that can be used in some other configuration.
safe
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An Example
http://digikey.com/scripts/DkSearch/dksus.dll?Detail?name=FDB8441CT-ND
FDB8441CT-ND
Fairchild Semiconductor
Current - Continuous Drain (Id) @ 25° C 80A
Rds On (Max) @ Id, Vgs @ 25° C 2.5 mOhms @ 80A, 10V
Power - Max 300W
Price for 100 - $1.31 each
So for each 12 volt battery unit the MOSFET price is:
4 * 2 * $1.31 = $10.50
If you are running a 48 volt system the price for MOSFET's is:
4 * $10.50 = $42
...which seems very reasonable.
Efficiency calculation:
0.0025 ohms / 4 MOSFET's * 50 amps * 4 units = 0.125 volts (voltage drop)
12 volts * 4 units * 50 amps = 2400 watts
0.125 volts * 50 amps = 6.25 watts
6.25 watts / 2400 watts = 0.2% Power Loss
http://digikey.com/scripts/DkSearch/dksus.dll?Detail?name=FDB8441CT-ND
FDB8441CT-ND
Fairchild Semiconductor
Current - Continuous Drain (Id) @ 25° C 80A
Rds On (Max) @ Id, Vgs @ 25° C 2.5 mOhms @ 80A, 10V
Power - Max 300W
Price for 100 - $1.31 each
So for each 12 volt battery unit the MOSFET price is:
4 * 2 * $1.31 = $10.50
If you are running a 48 volt system the price for MOSFET's is:
4 * $10.50 = $42
...which seems very reasonable.
Efficiency calculation:
0.0025 ohms / 4 MOSFET's * 50 amps * 4 units = 0.125 volts (voltage drop)
12 volts * 4 units * 50 amps = 2400 watts
0.125 volts * 50 amps = 6.25 watts
6.25 watts / 2400 watts = 0.2% Power Loss
