VOGONS


First post, by tomosap

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HI all,

Specs are as follows:

Pentium 4 1.7GHz Willamette (spec https://www.cpu-world.com/sspec/SL/SL6BD.html)
ASUS P4B533-VM Motherboard (states in the supported CPU list that this is compatible)
PC2100 RAM (this is where I think the issue lies)

So I've put all this together, I know the RAM works in an Athlon Mobo, I know the PSU works in a different build, so the only two parts left are the motherboard and processor. Both were sold as working, so I want to rule everything else out first. System won't POST/Beep/Nothing.

My first thought is that the CPU is designed to run at 400MHz (so DDR Ram would need to run at 100Mhz), so I figured it might be to do with the memory speed vs CPU bus speed. The motherboard has a jumperless feature, so I tried turning that off and forcing the bus speed to 100MHz. Nothing.

I know conventional wisdom suggests that you can underclock ram, but am I missing something in that the memory which I have (designed to run at 133MHz) won't run that slowly?

Grateful for advice from anyone else who's created a similar setup, or can throw a bone my way.

Tom

Reply 4 of 10, by texterted

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Clear the cmos and try powering on whilst holding down the DEL key on a ps2 keyboard.

Cheers

Ted

98se/W2K :- Asus A8v Dlx. A-64 3500+, 512 mb ddr, Radeon 9800 Pro, SB Live.
XP Pro:- Asus P5 Q SE Plus, C2D E8400, 4 Gig DDR2, Radeon HD4870, SB Audigy 2ZS.

Reply 5 of 10, by Doornkaat

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tomosap wrote on 2021-03-05, 14:38:

No beeps regardless of what's plugged in or not - tried with ram/without ram and nothing.

No beeps with no RAM makes RAM incompatibilities as the root of the problem less likely.
Sadly both a bad board and a bad CPU will cause this. If you don't have a POST card and no way to test the CPU in a known good board it's hard to say which of both is the culprit.

Reply 6 of 10, by Warlord

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tomosap wrote on 2021-03-05, 12:17:

My first thought is that the CPU is designed to run at 400MHz (so DDR Ram would need to run at 100Mhz), so I figured it might be to do with the memory speed vs CPU bus speed. The motherboard has a jumperless feature, so I tried turning that off and forcing the bus speed to 100MHz. Nothing.

No the board specifically states it runs on DDR266 or pc2100.

What you really want to do is find a set of DDR 2700 with tight timings. As tight as you find. Since it is backwards compatible with 2100. So When you run them in that board it will down clock them to 2100 and you can tighten the timings to like 2-2-2-5

There is a switchblock near the rear IO for external bus frequency. you need to set that at 100. For that CPU.

Reply 7 of 10, by canthearu

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One thing you should do is double check that the speaker cable is correctly plugged in.

Also Make sure you have the 4 pin CPU power connector attached. This is an easy mistake to make.

If you are using an old PSU, you could try a different PSU, even trying newer units.

If you have double checked you have done everything right, then you likely have a defective motherboard. Double check all the capacitors around the CPU, if they are buldging or leaking, you may need to replace them.

Reply 8 of 10, by tomosap

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texterted wrote on 2021-03-05, 15:40:

Clear the cmos and try powering on whilst holding down the DEL key on a ps2 keyboard.

Give this man a freakin' medal!! That worked, thanks so much - I genuinely didn't believe that would do it but it has, and I'm so pleased to be wrong 😁 🤣