presence detect and nanosecond

Hi. This is my 1st post. I searched, but really didn't come up with a compatible question. A pc I worked on has a default setting in bios of 60ns memory speed. This is not seen in bios, nor is it changeble in bios. I only know this by reading the mobo manual. I changed the memory from 60ns 72-pin 5V EDO SIMMS to 10ns 168-pin 3.3V SDRAM DIMMS. No jumpers involved. The mobo is an Aopen AP58(yes it's ancient). Of course, the bios picked up the amount of memory from the presence detect pins and got that correctly at 128MB from 64MB. How can I be sure the memory speed of 10ns was detected?. I have no way of confirming this. Oh, I did see one post in a search that might help. Some program at If I understood the post correctly it can tell you the nanosecound speed or the memory. Anyway I would appreciate thoughts on this subject unless this is another one of those ad naseum questions, don't bother to reply, I understand. Heck, on other forums I seemed to have answered questions about defragging and system resources on a daily basis. About system resources. I can run at 5 to 10% resources all year long and be perfectly content. And I know the difference between resources and memory. It's all in the heaps, man. Dig it. Thanks for your time in this matter.

editor-in-chief PC Voodo(one O on purpose)
owner and operator Voodo Child

p.s. the above musings about the Voodo stuff is a gag.
3 answers Last reply
More about presence detect nanosecond
  1. Hi. Well Bob, tweakfiles was a dead end. It has become some games site. People at Tech24 said 83mhz = 12.5ns. You can use this in a calculation to find a memory speed. Whether you're running 60ns or 10ns memory the fsb is still the same so how can I come up with a memory speed for the chip?. I went along with the girl and they took my money. I later complained and they said they would get back to me in 24hours, but they never did. It really wasn't a tech question anyway. Not for this day and age. Why does it matter to me?. Heck, I'm curious. If the bios has a default setting, that usually means it's set and can be changed, but has to be changed manually, I would think. I don't know, I'm no guru. If not, then what?. Change CAS, wait state, auto config?. On my Blaze Master I have zero wait states with 7.5ns DDR SDRAM PC2100 and a CAS of 2.5. Do I know what I'm talking about?. [-peep-] no!. What point am I making?. None. I just felt like getting rid of the zero(0) under replies. I'm supprised more people don't do it.

    RCH editor-in-chief PC Voodo
    owner and operator Voodo Child
    continuing to pull pins out of my head
  2. You switched from EDO to SDRAM? With SDRAM, the speed setting is not available in BIOS because it's Sychronous. In other words, it runs at bus speed. Such motherboards automatically switch from EDO settings to SDRAM settings, or else they wouldn't work!

    Frequency is 1/cycle time, so if your bus speed is 66MHz, your RAM will have a cycle time of 15ns. If your bus speed is 100MHz, your RAM will have a cycle time of 10ns. Even if you ran 6ns RAM, it would run at these speeds.

    Most Aopen boards have Cas Latency adjustments. Cas Latency is the number of clock cycles it takes for your memory to respond. Setting this to it's lowest value results in the highest performance, up to the limit of stability.

    <font color=blue>You're posting in a forum with class. It may be third class, but it's still class!</font color=blue>
  3. Hi. Thanks Crashman for the reply. I copied and pasted the answer, because I have to admit I'm going to have to study it for awhile. The elements aren't immediately clear to me. I have pages and pages of explainations of bios settings I'm going to have to jump into. I know the edo is asynchronous and know the mobo can be set up for async or sync running manually. Can't remember at the moment why the async setting was needed. I've set my own Aopen AK77Pro(A)-133 to CAS 2 and it ran OK. Its at 2.5 now. The lowest it can go is 2. Same with the AP58. It's at 2.5. My mobo has a CAS auto setting which is interesting to me. Don't know of a benefit there. As far as the AP58 goes, I'll change it to 2 after I upgrade the processor from 166mhz/mmx to 233mhz/mmx and beef up the video board substantially. All within the boundaries of the older Pentium that it is. Also I'm upgrading the AP58 bios to today's specs or a least to the limits of the AP58s performance. Got it from Unicore/Touchtone Software. I didn't want to pay what they first quoted. Less than a week later I recieved an email saying I could get it for $30.00 less. The original is flash, but I wimped out and didn't want to do it, even tho I have the files already for it.
    I've heard of programs which get at the hidden bios settings of a PC. The settings they think were to dumb to deal with. Could you recommend one?. I loaded one once and recieved a runtime error, like I know what that is. I've seen a few of them, tho. Everything test/diag has to be run from DOS. I enjoy DOS, but I'm also sick of it. At least Sandra can be run with Windows and I know a lot of others, but I just run into to much DOS stuff. Boy, I'm ranting and rambling on, but I don't care, I like talking to myself. I'm a good listener. Thanks for your time.

    RCH editor-in chief PC Voodo
    owner and operator Voodo Child
    pulling pins out of my head

    Raise our glasses against evil forces. Whisky for my men, beer for my horses.
Ask a new question

Read More

Memory BIOS