Mixing 128 with 256: RAM question

Factual Questions
1

Can you mix 128MB of RAM with 256MB of RAM on as Asus P2B-f motherboard?

I bought a 256MB SDRAM piece the other day and wanted to add it to my system. I currently have one piece of 128MB SDRAM. After I added the RAM and booted my computer, that first DOS screen listed my RAM as 384MB. It also
listed a message that said “Updating, EMI information, ESCD”. When Windows 98 loaded, I checked for the RAM settings in the Control Panel, and it too
said it was 384MB.

So it seems as my PC was recognizing my RAM. But I noticed two problems:

1/ The extra RAM didn’t seem to be making any noticeable speed difference. For instance, I timed the Win98 boot up (after I entered my Windows username/pass) at 28 seconds with 128MB, and 23 seconds with 384. Other tests I ran, just as opening up Photoshop and other big apps actually showed that my PC was slower with more RAM.

2/ The other problem was more annoying. Each and every time I tried to open the Control Panel from the Start menu, it took about 30 seconds for the Control Panel to open. During that time, my mouse still could move, but the Start button still looked like it was “pressed in”, yet I was able to open My Documents and others folders.

My initial suspicion was the RAM pieces were somehow conflicting. So I tried the 256MB alone in the first slot. Another time I added the 128MB in the second with it. Basically, I tried just about every combination, but always
with the same results. At this point, I think that the 256MB RAM is just no good for my PC.

Here is an overview of my setup:
Windows98 (first edition)
CPU: P2 350Mhz
Motherboard: Asus P2B-f (Bios 1008)
Bus: 100Mhz
RAM Slot 0: 128MB
RAM Slot 1: empty
RAM Slot 2: 256MB
RAM Slot 3: empty

Here is some info on the RAM pieces:

128MB 100Mhz RAM

  • it has 8 rectangle things on each side, for a total of 16
  • it has the following markings on it: 9902 MT TG
  • it also has these markings: 1-1 48LC8M8A2 -8E B
  • and it has a sticker that says: PC100 Q-165D64
  • I ran a diagnostic, but the brand was unknown

256MB 100Mhz RAM

  • it has 8 rectangle things on each side, for a total of 16
  • it has the following markings on it: 0050 MT TG
  • it also has these markings: 1-1 48LC16M8A2 -8E E
  • I ran a diagnostic, but the brand was “Zentrum”
  • Serial number was 4294967295

Also, the 256 is slightly wider than the 128. That is, when the RAMs are in the motherboard, it protrudes a bit more(maybe 1/4 inch higher).

BTW, I ran the Ontrack Data Advisor 5.0 hardware test on my RAM and it found no problems.

2

**

I don’t know about that specific motherboard, but if both sticks are PC 100 or PC 133 and they are both SDRAM, then you should not have any problems.

**

RAM will not make applications open any faster. That is due to processor speed. More RAM will cut down on the time it takes to do things within the application, once opened.

As far as everything else, mixing RAM by different manufacturers can cause issues. If you can buy another stick of 128 or even 256, if cost isn[t an issue, from the same place as you got your first 256 stick, you should be okay.

3

Yes you can. Here’s a link to the main page for your motherboard if you want to lookup more information.

The only issues I know of with mixing RAM types is:

  • Don’t mix gold and tin contact memory chips. The different metals have slightly different electric characteristics. Over time your memory could be damaged.

  • Different memory chips have different latency characteristics. You can get CAS 2 latency or CAS 3 latency chips (2 being better). You can mix and match these chips but the BIOS needs to know to run at the slower latency. This may be automatic or you may have to change this manually. To find the CAS latency you need to find documentation on the chip you are looking at. If in doubt set for the slower (CAS 3) setting (CAS 2 chips will happily run with this setting).

  • This may or may not be useful but try installing the chips in consecutive sockets and not every other one like you currently have it. It’s hard to explain why I think this might help (there are timing issues with memory) so just give it a try. It might help and shouldn’t hurt.

Beyond this your system seems fine in so much as the BIOS is reporting the memory (as is Windows).

It doesn’t sound like you are using error correcting (ECC) memory since those chips have 9 ‘rectangle things’ on them and both of yours have 8. Still, make sure your BIOS isn’t being told to try and use ECC (again…this may be automatic…I’m not familiar with the BIOS on that board and what it allows you to do).

As to Windows not loading any quicker remember that more memory is not a cure-all for speed. At some point the CPU is fast enough that it is waiting for other parts of the system to give it the data it needs. Memory is a bottleneck but the biggie is your harddrive. When booting all data needs to be loaded into memory and no matter how fast you CPU is or how much memory you have both will be waiting on the harddrive to hand out its data.

Where more memory gives you a speed advantage is in avoiding having to swap data to and from the harddrive. If you open a lot of applications at once or use memory intensive applications (such as Photoshop can be) the computer may run out of system RAM to use. When this happens it writes data to a swap file on your harddrive that the computer is tricked into thinking is like main system memory. This swapping to the disk is, however, MUCH slower than using system RAM. If you notice your harddrive getting thrashed alot (the light is constantly blinking and your mouse tends to jump and skitter) then you may be a good candidate for more memory.

However, if all you ever do is surf the web and write e-mail then more memory beyond 64MB sin’t likely to net you any noticeable performance improvement.

Your other issues (Photoshop being slower, Control Panel not opening) sound like something’s up with your operating system. More memory shouldn’t cause these problems unless your memory chips are flaking out. Try going here and updating your OS. If you have a slow internet connection this could take a LONG time depending on what you all need (also, don’t forget to update Internet Explorer even if you use another browser…that program is tied deeply into the OS and I have fixed totally unrelated problems by updating IE).

Good luck.

4

In a weird cosmic coincidence, I, too, bought a 256MB DIMM for my ASUS motherboard yesterday, and tried to add it to my already existing twin 128MB DIMMs. My computer is fairly old, a P2 450, and I wasn’t able to buy RAM that ran at 100Mhz. However, the slippery salesman told me, the 256MB 133MHz DIMM will run just find on my system.

Wrong. Computer refused to boot up at all. Take the 256MB out, boots up fine. Stick it back in, locks up. I tried swapping the slots, rearranging their order. Nothing worked. Today I take it back with some choice words for the salesman.

5

I’d have expected it to work too. Did you set the memory latency (CL) to 3 in the BIOS setup?

6

Seraphim, a PC133 DIMM should have worked just fine for your P2-450. I can’t think of why it wouldn’t work… unless there is somthing screwy with the CAS settings in your BIOS or something… just a thought. Maybe bring your PC with you when you return it or call ahead.

As for the JDL, as mentioned your loading speeds probably wont decrease but once the application is running, if its a memory hog it should run quite a bit faster.

Another trick you might want to do is the conservative_swapfile_usage=1 or whatever it is command on startup. I can’t remember exactly what it is and where it goes, but if you do a search on swapfile tweaks you should find it. It tries to force Windows to use more memory before hitting the hardisk for virtual memory. If you have over 256MB RAM it can help out.

Just a couple points :slight_smile: