scott@max.u.washington.edu (08/23/90)
Hello,
I have an 6-Meg 386 computer that I have purchased a year ago or so.
It has been work almost flawlessly since then, but still have few
questions that I hope someone could help me with.
Originally the 386 came with only 1-Meg populated on the motherboard
with 256K-1bit-80ns chips. Since then, I have added an additional
5-Meg of memory in the following form:
Motherboard
1 Meg of 256K-1bit-100ns
Add-on board
3 Meg of 256K-1bit-100ns
1 Meg of 256K-1bit-150ns
My 386 has a clock speed of 20Mhz, switchable to 25Mhz turbo mode, and
it has a buffer cycle of 8Mhz.
As you can see, I have several different time-rated chips in my computer,
most of which are above the recommended 80ns.
My question is this: Is there any danger or problems to my computer that
I should know about if I want to keep my computer with these memory chips?
Is this only a prelure for an impending break-down of my computer?
For the few months since I had this setup, my computer has worked fine
for all applications, including Windows 3.0. However, since I will be doing
some lengthy works on my computer, it would be catastrophic if my
computer would start suffering from chronic crashed or breakdowns,
especially in the middle of my work.
Any comments will be appreciated.
Thanks in advance.
Scott K. Stephenprk@planet.bt.co.uk (Peter Knight) (08/23/90)
scott@max.u.washington.edu writes: >Originally the 386 came with only 1-Meg populated on the motherboard >with 256K-1bit-80ns chips. Since then, I have added an additional >5-Meg of memory in the following form: > > Motherboard > 1 Meg of 256K-1bit-100ns > > Add-on board > 3 Meg of 256K-1bit-100ns > 1 Meg of 256K-1bit-150ns > >My 386 has a clock speed of 20Mhz, switchable to 25Mhz turbo mode, and >it has a buffer cycle of 8Mhz. > >As you can see, I have several different time-rated chips in my computer, >most of which are above the recommended 80ns. >My question is this: Is there any danger or problems to my computer that >I should know about if I want to keep my computer with these memory chips? >Is this only a prelure for an impending break-down of my computer? >For the few months since I had this setup, my computer has worked fine >for all applications, including Windows 3.0. However, since I will be doing >some lengthy works on my computer, it would be catastrophic if my >computer would start suffering from chronic crashed or breakdowns, >especially in the middle of my work. >Any comments will be appreciated. > >Thanks in advance. > >Scott K. Stephen Yes and no. Most chips are not designed to work at a variety of speeds they are selected by the manufacturer at post production test. The manufacturer tests them over a variety of temperature and power supply conditions and then attaches his reputation to the parts that he sells. Hence it is perfectly possible to have 100ns part work alongside 80ns parts without problem. However, you have no comeback if it does not work. If you are worried about crashes, my advice would be to use 80ns memory only on the mother-board, if that is what the PC manufacturer calls for. As for the expansion board, these run a lot slower: This is because they need a lower overall clock speed either for compatibility or for electromagnetic interference reasons. This may not apply if the memory cards plug into something other than an XT, AT or MCA bus. Again, if you are concerned, check with the manufacturer of the expansion card. Peter Knight BT Research #include <std.disclaimer>
poffen@sj.ate.slb.com (Russ Poffenberger) (08/23/90)
In article <14202.26d270cf@max.u.washington.edu> scott@max.u.washington.edu writes: >Hello, >I have an 6-Meg 386 computer that I have purchased a year ago or so. >It has been work almost flawlessly since then, but still have few >questions that I hope someone could help me with. > >Originally the 386 came with only 1-Meg populated on the motherboard >with 256K-1bit-80ns chips. Since then, I have added an additional >5-Meg of memory in the following form: > > Motherboard > 1 Meg of 256K-1bit-100ns > > Add-on board > 3 Meg of 256K-1bit-100ns > 1 Meg of 256K-1bit-150ns > >My 386 has a clock speed of 20Mhz, switchable to 25Mhz turbo mode, and >it has a buffer cycle of 8Mhz. > >As you can see, I have several different time-rated chips in my computer, >most of which are above the recommended 80ns. >My question is this: Is there any danger or problems to my computer that >I should know about if I want to keep my computer with these memory chips? >Is this only a prelure for an impending break-down of my computer? >For the few months since I had this setup, my computer has worked fine >for all applications, including Windows 3.0. However, since I will be doing >some lengthy works on my computer, it would be catastrophic if my >computer would start suffering from chronic crashed or breakdowns, >especially in the middle of my work. >Any comments will be appreciated. > I wouldn't say a "breakdown" but you are more likely to get memory errors during use. A memory error will probably crash the machine requiring a reboot. The problem may tend to get worse with age, and while in turbo mode. Russ Poffenberger DOMAIN: poffen@sj.ate.slb.com Schlumberger Technologies UUCP: {uunet,decwrl,amdahl}!sjsca4!poffen 1601 Technology Drive CIS: 72401,276 San Jose, Ca. 95110 (408)437-5254