Upgraded to Round Cables...

[greekgeek]

Hey guys, I've been lurking in the Forums for some time now, and this is my first post.

My main rig is an Athlon XP 1800+ that I built last January. Right now it sports 768MB RAM, a Quantum 9.1GB SCSI & WD 20GB IDE HDDs, and DVD-+R/RW. Yesterday I decided to upgrade to Round cables (for the IDE bus only) to lower case temp and that's when things started being weird. According to HDTach (before the change) the Read Burst speed was 92MB/s for the SCSI and 90MB/s for the IDE disk. Now after installing the new cables (ATA-133) I get a max of 84.5MB/s for either drive.

Assuming that the previous ribbon cables were better, what happenned to the SCSI bus? I didn't even touch it!

Any thoughts?

 

[MDE]

Have you tried to remove the cables and plug them back in? You may have slightly jarred one loose.

 

[greekgeek]

All cables secure, disk fragmentation at 0%, DMA still enabled, no other changes made.



/scratches head, wondering why did I need to "upgrade" a perfectly healthy system/

 

[MDE]

Try moving the IDE cable around, it may be interfering with the SCSI cable or vice-versa.

 

[0roo0roo]

technically round cables should be more prone to error right? the 80 wires on the normal flat cable are actually 40 data with 40 more to preserve integrity... but looks and practicality....round is fast enough

 

[airfoil]

Cant substantiate this, but I read somewhere that round cables eat performance.

 

[GtPrOjEcTX]

yet another reason not to get round cables (on top of the reason that you can get better airflow from regular ide cables when they are folded properly)

 

[Lonyo]

Performance on my 80GB WD and 80GB Maxtor stayed almost exactly the same, 40MB/s on the WD, 50MB/s on the Maxtor - exactly the same as with normal cables and round cables, access times were the same as well, not sure about burst, but that looked "similar" at ~90 and ~80MB/s for the drives.
Didn't find any performance loss. Try switching back to the flat cables and see if performance changes?

 

[sharkeeper]

Probaby a dodgy, poor quality cable.

I've used them with no ill affect. I have had bad ones that kill performance or flat out refuse to work, however.

One of those were U320 SCSI and the HBA was throwing exceptions due to media errors. Once the cable was swapped out, the error log tables reset, everything was fine.

All of the SCSI benchmarks I post are done with rounded cables so I do have confidence in them.

Cheers!

 

[EarthwormJim]

Have you tried using your old cable? There's nothing wrong with round cables, it's just there are many cheap quality ones.

 

[InlineFive]

I think the problems with round cables are since that all the cables are crammed together there is a much higher chance of electrical signals crossing from cable to cable. Regular IDE cables don't have this problem. And if you want the airflow do like I did and buy a PATA-to-SATA adapter.

-Por

 

[sharkeeper]

I think the problems with round cables are since that all the cables are crammed together there is a much higher chance of electrical signals crossing from cable to cable. Regular IDE cables don't have this problem. And if you want the airflow do like I did and buy a PATA-to-SATA adapter.

Properly made cables do not have this issue as the conductor pairs are twisted. If the cables are home made (i.e. made by separating the pairs and taping them together and wrapping them) this issue can occur.

Cheers!

 

[EeyoreX]

I am going to agree with some of the other posts, try different cables. I have used round cables for years with no effect. Unless maybe there is some performance lost when I benchmark my system. But since I have better things to do with my computers (like use them) I don't sit around and bother with a synthetic benchmark. Bottom line: Try a different cable, either a different rounded or different flat one. ANd use quality cables.

\Dan

 

[greekgeek]

Thanks for all the replies guys!

After a sudden BSOD, and subsequently a "NTLDR missing" I went back to my trusty good ole' ribbon cables and everything is happy again.

Now the round cables are being shipped back and the lesson of "don't mess with a perfectly working piece of hardware" is one step closer to being forgotten again...

 

[warcrow]

Originally posted by: PorBleemo
I think the problems with round cables are since that all the cables are crammed together there is a much higher chance of electrical signals crossing from cable to cable. Regular IDE cables don't have this problem. And if you want the airflow do like I did and buy a PATA-to-SATA adapter.

-Por

Yup. They don't meet the IDE specs if I recall correctly. So there is some EMI going on.