Performance after a memory upgrade

[eburnette]

I recently bought an IBM T42 Thinkpad notebook (1.7Ghz Pentium-M, 2378FVU) with stock 256MB in it, and bought two Kingmax 1GB sticks from newegg.com to put in it. All the memory was rated PC2700 CL2.5. Before upgrading I ran the Sandra memory bandwidth benchmark (http://www.sisoftware.net/) and got these results:

Buffered int 2268MB/sec, float 2278MB/sec
Unbuffered int 2004MB/sec, float 2020MB/sec

After upgrading I got this:

Buffered int 2260MB/sec, float 2017MB/sec
Unbuffered int 1436MB/sec, float 1440MB/sec <== ~ 30% reduction

After upgrading, the Sandra memory info says there are "4 banks of 512MB" running at "2.5-3-3-7CL 1 CMD". I didn't write down the timings before the upgrade but I remember it said there were "2 banks of 128MB". I couldn't find an option in the Thinkpad Bios to adjust the timings.

My question is, is this normal or should I return these and get some higher priced brand name memory sticks instead? Or do I have to shell out the money for the ultra-expensive IBM memory to get top performance? Would 2x512MB sticks be faster than 2x1GB sticks (I may have to buy less memory if it's more expensive anyway, but 1GB would probably be enough for a while)?

Thanks,
--Ed

[eburnette]

Anybody have an idea on this, or is this the wrong forum?

[BillMorrow]

i don't think kingmax is particularly cheap or bad memory..
how much was it anyway..??

just for laughs, try one and then the other memory parts..
and run the tests again..

also, common logic says to reseat memory..

[Plinkerton]

You definitely don't need to, and never should, buy the IBM ram. It's just overpriced. I have a 2378-FVU also, and I threw in 512 of crucial ram when I got it. You definitely have more than enough.

Can't help you with the other questions though...

[brewt]

You definitely don't need to, and never should, buy the IBM ram. It's just overpriced.

Unless they have a sale I got a 512MB stick added to my 2378FVU for $99 ($10 cheaper than Crucial). Too bad they're not offering that special right now.

[JHEM]

Unless they have a sale I got a 512MB stick added to my 2378FVU for $99 ($10 cheaper than Crucial). Too bad they're not offering that special right now.

So you've got 768MB in the unit now rather than the 256MB that came standard?

If they added 512MB to your unit that's a good deal. But if they substituted the 512MB stick for the 256MB that the unit normally comes with, then it's no bargain at all!

Regards,

James

[eburnette]

Regarding how IBM does memory upgrades when ordering, my experience has been that they add it not replace it. But I believe you can tell for sure on the final parts list.

Regarding price, the Kingmax 1GB sticks were $191, no shipping or taxes. It's gone up a few dollars when I just checked newegg (197+4.73ship). I would have considered Crucial but theirs was $365 and IBM's was $599!

Regarding memory timings or BIOS settings, nobody has answered that one yet.

Regarding stability, except for some crashes running Doom3 the system has been pretty stable.

Regarding memory use, I'm not using anywhere near 2G myself but Windows will use any leftover memory for file system cache so figure, half for you and half for cache.

So unless somebody can run the trial Sandra memory bandwidth benchmark and tell me they're getting better numbers and timings with 1GB or 2GB than I am (esp. when turning buffering off) then I guess I'll leave it alone.

[eshtog]

this is off topic, but how long did it take you to get the laptop and where was it shipped from?

[eburnette]

4 days from order, shipped from KOWLOON BAY, HK.

[brewt]

So you've got 768MB in the unit now rather than the 256MB that came standard?

If they added 512MB to your unit that's a good deal. But if they substituted the 512MB stick for the 256MB that the unit normally comes with, then it's no bargain at all!

Yup, 768MB total.

[ZPrime]

if you're using kingmax from newegg, be sure to run it through memtest86+ for an hour or 5. I got a pair of 512M dimms (PC3200, just because) for my T42p and one of them was dead on arrival. Actually, not dead, just had a bunch of bad addresses on the RAM that were causing crashes and all sorts of other weirdness. I got a replacement stick from newegg and now it's all fine.

I'd highly recommend running it through memtest, because it could indeed be faulty...

the other thing is that you have > 1GB of ram. some chipsets have to change their timings to accomodate more than 1G, or sometimes using both slots does this.

[eshtog]

4 days from order, shipped from KOWLOON BAY, HK.

man this is bs, mine shipped on oct. 28 and i still havent got it, its been stuck in customs for a week

[Kenn]

the other thing is that you have > 1GB of ram. some chipsets have to change their timings to accomodate more than 1G, or sometimes using both slots does this.

I believe this is right - it's been reported and articles on hardware sites have shown it to be the case, especially if you're running the maximum RAM supported.