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Thread ID: 22925 2002-08-03 05:26:00 Low bandwidth efficiency? B.M. (505) Press F1
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67746 2002-08-03 05:26:00 I have long held the opinion that my old Pentium 166 may not be running at full speed .

I just run a programme called SANDRA which reports: “Low bandwith efficiency (legacy) check memory timings & settings”

I think it was testing Memory – Chipset

Can anyone suggest what this is all about?

Could there be some Jumper settings that are wrong . Regretfully the computer is second hand and I don’t have any documentation for the motherboard .

Processor: 167mhz Intel Pentium

Memory: 256 SDRAM 66mhz Data Rate

Chipset: Intel 82439tx 430tx system controller

Cheers

Bob
B.M. (505)
67747 2002-08-03 05:36:00 With 66mHz ram access speed you were expecting....what? godfather (25)
67748 2002-08-03 05:40:00 If my memory serves me well (and more and more it isn't), the Intel TX chipset is only capable of cacheing 64MB of memory. Therefore increasing memory above 64MB can actually produce a performance degradation! (If you have ever tried running a PC with cache disabled (in bios), you will know what sort of performance hit it makes. Unless you have application requirements for 256M of ram, try reducing the RAM to 64M - you may find its better! wuppo (41)
67749 2002-08-03 05:41:00 B.M.

There may be some help here: Memory (www.sisoftware.demon.co.uk)

or here sisoftware sandra (www.sisoftware.demon.co.uk)

Babe
Babe Ruth (416)
67750 2002-08-03 09:23:00 Thanks Godfather, Wuppo and Babe Ruth .

Starting at the top .

Godfather this machine is the Tiger Moth of PC’s, it is not for Lear Jet Pilots . Having said that I thought it might be significantly quicker than my AcerNote Light . (133mhz 48meg RAM . ) I guess in fact it is, but there is no need for a stopwatch . An egg timer is just fine .

Wuppo, come to think of it I have heard that you can over kill with memory . There are just two 128meg sticks so it is a little difficult reducing it to 64meg . Any point taking one out?
Another thing that I can’t quite follow is according to “diskfronter” the swap file has never been written too . !? Normal use is XL with 4 or 5, 2meg sheets open at a time, with lookup’s between them . I think the diskfronter programme may be right as the only time the HDD light comes on is when I save . My concern was that there may be a jumper that should be set at X2 or something and isn’t?? (I can’t see anything on this Motherboard that says Xanything

Babe Ruth, I looked where you suggested . It was sisoftware Sandra that advised I had “Low bandwidth efficiency” (legacy) “Check memory timing and settings” Other than that everything was as good as could be expected . Unfortunately, the website explanation is way above my head and doesn’t suggest what one should do to correct the bandwidth efficiency .

You know prior to coming across this website I used to only fix things when they were broke .
Now I read all these articles and have become a bloody twiddler . Nothing’s sacred anymore . Yea, overclocked, jet propelled, Tiger Moths, that’s the story . Geeeeeeeez I should be flogged!

Oh well, better get emotionally prepared for the footy,

Cheers

Bob
B.M. (505)
67751 2002-08-03 11:13:00 B.M. Reducing mem to 128MB will still leave 64MB uncached. You are better off with more memory and no swap activity! The system clock is / should be running at 66MHz to give your 167Mhz processor speed, so is optimal for the Ram speed. No magic 'x2' jumper ! :-( Sandras memory efficiency rating is based on measured throughput against the theoretical throughput of the memory width at the memory clock speed. The newer chipsets achieve much higher 'bandwidths' and so, in a comparative sense, the TX is reported as sluggish. Bottom line - if it works and does what you want - just use it. wuppo (41)
67752 2002-08-03 23:19:00 Thanks for that Wuppo, what a blow, nothing to fiddle or twiddle!

Must admit I have been poking around in the CMOS set-up, (I thought it might be a good idea to check that the cache you mentioned in an earlier post was enabled. It was.) and I find the following.
C8000-CBFFF Shadow Disabled
CC000-CFFFF Shadow Disabled
D0000-D3FFF Shadow Disabled
D4000-D7FFF Shadow Disabled
D8000-DBFFF Shadow Disabled
DC000-DFFFF Shadow Disabled

Thought hmmmmm wonder what happens if I enable these, but then thought maybe it might pay to ask first, seeing I’ve no idea what the relevance of these settings are.

Must admit I found the PCI/VGA Palette Snoop was disabled and a book I have says that enabling it allows the Video Card to directly access RAM so I thought ahhh I’ll enable it and see what happens. Unfortunately, when we got as far a the windows screen all I got was fluffy white clouds and the HDD light flashing about every 5 seconds. Sat like that for about 10 minutes before I decided we weren’t going anywhere and pushed the reset button. Yes, then had to go and sort out the mess I’d made with my undignified exit. Needless to say PCI/VGA Palette snoop is now back to disabled.

Any thoughts on these matters would be greatly appreciated.

Bob
B.M. (505)
67753 2002-08-03 23:46:00 The shadow settings are only of use if you run dos, all are in the 640-1024kb range of memory. And the ones you listed are only of use if you have a piece of hardware that is using one of those ranges.

The bios optimisation guide is a good reference, there are download links at the botton of this page.

www.google.co.nz
bmason (508)
67754 2002-08-04 04:19:00 Those shadow settings allow copying any BIOS extensions which are held in ROM on peripheral cards into R/W memory. ROMs are much slower than R/W memory. Usually, VGA, SCSI, and Ethernet cards used that. Linux doesn't bother --- can do it better --- and the modern MS stuff probably doesn't. Graham L (2)
67755 2002-08-04 06:34:00 Thanks bmason & Graham L .

I went to that site and downloaded and printed the whole 67 pages . Very interesting .

Yes Graham it confirmed your explanation of the shadowing .

I made a few adjustments as recommended and went to Nortons System Works to admire my handiwork . Bahhhhh .

Prior to my twiddling the benchmark for a Pentium 167mhz was 37, my system was 26 .

After twiddling my system improved to 27, bid deal!

Oh well, it was very therapeutic, not to mention educational .

Cheers

Bob
B.M. (505)
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