What's holding me back?

Hello!

I just got in a stick of 256MB Kingmax PC-150, which is replacing my Micron PC-133 CL3 RAM.

With my old RAM, I could OC to 156 MHz FSB, RAM 3-3-3. Slight instability in games, but perfect everywhere else. Whenever I tried to boot higher, I usually got CRC errors, file corruption errors, and the like when I booted up windows or linux. Same thing would happen if I tried to boot up at CL2 at too high a FSB.

With my new RAM, I booted up at 156 MHz FSB at 3-3-3 (just starting to test.) It ran with better stability, even in games. However, it wouldn't post at 3-3-3 at 160 MHz FSB. I haven't tried 157-159 yet.

My CPU temps are always on the order of 41-45C, so temperature is not a problem.

Other components:
Creative SBlive! 5.1 (sound crystal clear at 156 MHz FSB)
PNY GF 2 MX-400 AGP (fine)
WD HDD
Shuttle AE-25 i815ep-b0 chipset
CD-RW,

All in all, standard stuff.

So, what's holding me back at speeds like 160 MHz? I've noticed that the northbridge is passively cooled with a heatsink. (It appears to be glued on -- I don't see any way of getting it off.

Any ideas on what's holding me back?

Thanks! -- Paul

It's most likely to be your HDD. Try disabling DMA, and use PIO and see if you can boot into Windows with that FSB. WDD doesn't like high fsbs at all. Do not be surprised that it will take long since PIO is a major draw back from DMA. If it doesn't post, reset the cmos. Have you tried adding voltage to the ram?

Yodums

yep.. it's probably your hard drive. Hard Drives don't like very high PCI bus speeds. Check to see if you can change the mult in your bios or set the PCI and AGP clocks to a fixed clock. But I don't think your board supports that..

Overclocker456 said:

yep.. it's probably your hard drive. Hard Drives don't like very high PCI bus speeds. Check to see if you can change the mult in your bios or set the PCI and AGP clocks to a fixed clock. But I don't think your board supports that..

Click to expand...

Yodums & OC'er:

Hello!

Thanks for writing me back!! What you write is certainly reasonable. That would explain the 157 MHz buffer. (About 39 MHz on the PCI clock, AFAIK.)

I don't think that any ratios are available to be set, but I can be wrong, since it's the performance BIOS. I'll have to take a look.

I don't really feel comfortable with overvolting the RAM or CPU, so I'm pretty much limited to a FSB overclock. I was mostly just curious to see if it would post at 160 MHz FSB. I'll have to check for ratio settings, though.

I'll also see what a PIO setting does, just out of curiousity. It seems to be the surest way to determine if the HDD is the party-pooper.

Thanks again for your responses!

BTW, regarding the Kingmax, it's beautiful! I just ran a 4 1/2 RAM diagnostic (memtest86), and it came out flawlessly at 156 MHz, 3-3-3. I almost got it to run flawlessly at 145 MHz 2-2-2 (a small bitwise error 251 MB into the RAM on test 5), but it runs 2-2-2 at 138 MHz just fine. So, I might go with the mild 138 MHz overclock with optimized memory bandwidth. I think I'll just run a few calculations and see how the bandwidth compares at high fsb, slow timings to low fsb, fast timings; I'll choose the optimal value.

Yodums, it's always a pleasure (reading your posts) ... -- Paul