Problems with 8k5a2

[SiFu]

ok I just put a new system together with the intention getting into overclocking.....it is as follows

epox 8k5a2
1800+ Tbred
2 x 256m samsung 2700
msi gforce 4 ti 4600
80gig wd with 8m cache
antec true power 480watt
(cant remember the stepping on the chip but it started with az.....)

first of all i had a hell of a time installing win xp - ended up having to disable sse in the bios - a bit of time on different forums told me this is a common problem with winxp combined with that chip and mb

now i dont seem to be able to really overclock at all.......first i tried setting vcore to 1.525 (1.50 defult) and vdimm to 2.6 (2.5 defult) and bumping the fsb up to 140, no worries there so long as my memory settings are on fastest (turbo settings wont work at all even un-overclocked) next i tried lowering the multiplier right down to 9x and increasing the fsb to 166 but it wont post at all, i turn on the machine and get nothing but a blank screen and am forced to reset the bios via jumper, it dosn't seem to make any difference even if i bump the vdimm voltage up by another .1 or .2

now this is my first ever attampt at overclocking so am i doing something wrong? but even then i should be able to use turbo ram settings on an un-overclocked setup shouldn't i?

i suspect that i have a dodgey piece of equip somewhere as even when not overclocked (or only overclocked to 140) unreal t2003 seems to crash quite a bit and prime 95 gets errors after only minutes

i have flashed my mb with the latest bios, downloaded the latest via 4 in 1 drivers and all that

i only have stock cooling but my temps dont seem to go past 40

any help would be appreciated

- ben

 

[SiFu]

anyone?

 

[RnPgrosz]

Did you re-enable SSE? When you say you had a hard time installing WinXP could you be a little more specific? Did you get BSODs, missing files etc.? I just had a similar problem and it turned to be a bad stick of memory. I would set the memory timings back to normal but do it manually. Don't use the normal, fast or turbo options to change the timings (they have been known to cause problems). I would recommend increasing the FSB step by step and see where you encounter instability, I have a feeling your memory may be bad. Also lower the multi so you can rule out the Tbred being the culprit. www.docmemory.com has a good program that will stress/test your memory for errors.

 

[a1cnolan]

well i have a 256 of samsung 2700 and i will tell you i cannot run turbo either or ever for tha matter no mater how low my clock is. i just found that i can go to 180 with my samsung on regualr settings and i don't know how higher as i just found out this might be possible a couple of minutes ago. but yeah mine wont run turbo. its not rated for it either. it says 2.5 and t means it to me

 

[AlexG]

I have this motherboard also, and a 2400+ tbred (b). I think you have a tbred "A", not a great overclocker by and large. The 1800 "B" is much better.

Have you unlocked the 1800+ chip? Didn't see where you mentioned it. That board will not let you change multipliers until you do. There is a way to unlock it but you have to physically connect some contacts on top of the CPU. The board failing to start is normal when you change multies. If you turn on 'watchdog' feature in BIOS you will at least get an automatic restart after boot fail.

Until you unlock you must use FSB only to OC! What chip speed do you hit at 140mhz? That might be all you can get from that chip. My 2000+ won't stably run past 140 either. That's a fairly typical problem with the "A" version of the tbred. They weren't great clockers. The "b" ver is a different story. I think you have the A ver. because 1.5 vcore was stock for it. 1.60 for the b.

Not sure about turbo but don't push it - if memory runs on "fastest' or 'fast' un-overclocked you are OK. You can check your RAM by going to www.memtest86.com and running their little program. You should probly do this, just to rule out flakey RAM.

While overclocking set memory timings to failsafe, i.e. slowest

Keep in mind that at 140mhz you have OC 11.5 times 7 mhz = 80mhz OC. Which is probably something well over 100mhz in PR terms. Giving you a 1900+, which is an OK OC for the old tbreds.

Plese note: I'm a little foggy about the 1800+ steppings and versions. Find out if you have a tbred b (13 micron). I think not.

You might need more vcore, 1.65 is a quite safe level (+10%). Try taking it up some. + 10% is always safe. Also stock cooling may be too weak.

One last thing. Did you install the heatsink/fan? It is VERY common for the HSF to be put on slightly askew such that it does not hit the cpu perfectly. This will stop you cold.

Buy an 1800+ B if you want serious OC. Or get a 2400+. Mine runs at 2900+ level on air cooling only.

 

[SiFu]

Thanks everyone for all the help

after alot of browsing on the amd/aoa forums, a couple emails to epox support and a bit of playing around i've got it all sorted

the problem is that (apparently) some combinations of 1700+ or 1800+ tbred a cpu's with an 8k5a2(+) mb and win xp/2000 result in a bizzare compatability problem and a very unstable system.....epox hasn't yet worked out whats up

but i am putting together a system for a friend and in it is going a 2400+ so i tried it out in my system, is currently in now, turbo settings run fine when not oc'd and at the moment it is running fastest @175x12 2.7 vdimm and 1.775 vcore....i can get it to 195 with normal settings (same vdimm) might try to increase the vdimm and see what i can get

anyways it seems i just need either a new cpu or mb....whichever one the place i got all the bits from wants to swap

have a good one

 

[SiFu]

alex: i believe all tbred under 2100+ are factory unlocked for multipliers 13 and down

 

[jlin453]

I'm guessing the xp1700+ Tbred B's will have the same problem with the 8k5a2's?

 

[juliendogg]

the problem is that (apparently) some combinations of 1700+ or 1800+ tbred a cpu's with an 8k5a2(+) mb and win xp/2000 result in a bizzare compatability problem and a very unstable system.....epox hasn't yet worked out whats up

wow, this is dissapointing, i was looking into a low speed t-bred b when i could find one...

 

[jlin453]

Are the problems with the Tbred's only w/the 8k5a2's or ALL epox boards?