Slot 7 Processor Upgrade query

[Silverguy]

I have an old HP Vectra with a slot 7 75MHz Pentium. How can I tell if it runs at less than 3.3V required for a 200MMX upgrade or should I just look for an overdrive processor.
If I put in a standard 200MHz MMX I'm frightened I might fry it..! The query results from the following info obtained from this site on slot specifications. http://www.pcguide.com/ref/cpu/char/socketSocket7-c.html

specifically the quote
"Socket 7 motherboards were the first to incorporate integral voltage regulators modules, to supply the lower (sub 3.3 volt) voltages required to internally power newer generation processors. Not all Socket 7 motherboards support the lower voltages, however; it was up to the motherboard manufacturer to plan for the future and make this flexibility an option, and not all of them did this before the first Pentium with MMX was released that required sub-3-volt power. Intel produces a Pentium with MMX OverDrive to be used in motherboards that don't support the 2.8 volt power requirement natively.

[saphalline]

It probably won't work as the P75 came out long before the P166 MMX, and in fact runs on the weird FSB of 50MHz, which was later replaced by the 60MHz and 66MHz FSB. The P200 MMX requires a 66MHz FSB. If your HP actually has a name-brand motherboard, then it might be able to handle a P200MMX, but otherwise you'll have to look up the serial number on it. There's a few posts about that somewhere in the forums...

You could probably go up to a P150 because it uses the same 50MHz bus, but I would not recommend an overdrive processor. Not only is the minimal performance gain outweighed by the high cost, but they generally don't have a good track record in quality and compatability (they automatically void any warranty because they are essentially 'overclocked').

Just turn it into a Linux machine.

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"No, we do not gnaw on our kitty." - Dr. Evil

[Stevie Blunder]

I had to re-check the post date on this one. Today, mid 2002, the sweet spot for computing value is about a 1GHz P3 with 256Meg of PC100 SDRAM, a 40G drive and a 24x10x40 CDR, ie well beyond a 75MHz CPU and a 50MHz FSB. Maybe your situation is special, but I would look at replacing the whole motherboard, if anything. Parts add up fast. There is no way that old mother board could be upgraded meet the minimum specs for a current version of Windows.

The fastest CPU for socket-7 is the AMD K6-3, but the clock multiplier is x6 max. That means 300MHz on a 50MHz FSB, but these chips are meant for 100MHz FSB, ie up to 600MHz core clock.

There are core voltage control pins on most socket-7 cpus, but many old boards ignored them and use jumpers to set the core voltage. Look carefully at all the mobo jumpers.

There are so many problems upgrading past the vision of the original design. Some are: BIOS support of faster CPUs, on chip cache support, EDO DRAM only, ISA/PCI slots, etc.

If you really want to DIY, I suggest you start with a new (cheap)motherboard.

[Paleo Pete]

Stevie Blunder: Sometimes you have to make do with what you have...and if you happen to have the parts handy, older machines are perfect to learn on. If the person wants to try and make something of the existing hardware, let's do our best to help make it happen.

A P-75 should run Windows 95, but maybe not all that great in the performance department. If it can be upgraded to 166 or 200MHz, MMX or not, it should handle Win98...Most motherboards that will handle a P-75 will handle up to either 133 or 233. Some support MMX, some don't but we can probably find out. The MMX will run on standard Pentium voltage, but will be flaky and will run hot. I DO NOT recommend trying it...not for more than a few minutes anyway...

Silverguy: If the computer will boot at all, at least to the first screen, press the [Pause] key to stop it during the memory count. Look at the bottom left and you will see a long number, that's the BIOS ID String. Write it down. Make a note if it is Award or AMI BIOS. Press any other key to resume booting.

Take the BIOS ID string to Wim's BIOS (http://www.wimsbios.com) and look up the motherboard, you might be able to find a manual that will tell you what CPU speeds and voltages it will support, and jumper settings for them.

If you can't find a manual, let us know what board it is, we may be able to locate one. Let us know and we can go from there.

[Stevie Blunder]

I quite agree with Pete if the parts are free, or nearly free. But if you can get a 200MHz CPU cheap, get a newer mobo from the same source. The price of parts that are this old, tends to a premium because they are selling to "captive" customers.

About a year ago I rolled a iHX embedded design to the iTX. Both these are OLD intel chipsets, but the TX supports SDRAM, which cut our DRAM cost from $300 for EDO, down to $70 for SDRAM, per unit at that time. Now, SDRAM is about $15 and I hate to think what you'd have to pay to get EDO DRAM today.

You can buy a BX mobo for about $25, 128M SDRAM about $15, and an ~800MHz CPU about $50. If the mobo has sound and video, that's about all you need. But the HDD that came with a 75MHz PC was probably less than 1G, so thats the other thing to change. Today, PC stores are selling off 40G drives as "loss-leaders". Smaller drives, if you can find any, fall under the "free after mail in rebate" catagory.

A couple years back I needed a CDROM drive. A local surplus store wanted $100 for an old 2X drive. Instead I bought an 8X drive from compUSA for $40, c/w free ISA IDE card.

I wandered around a couple local "referb" vendors. They want too much for old stuff that has a high probability of defect. Remember, these people are looking to recover money that someone spend badly. Instead, I recomend buying sale items from vendors that will give you your money back if you have a problem, ie big name stores. :rolleyes:

Department stores do not have the best prices on computers, but they will take almost anything back, any time. They throw it in the trash and take the loss. Big computer stores are almost as good about returns. Many small computer stores are just as good, but you have to be careful. A small company in finacial trouble is the most likely to shaft you, or refuse a marginal return.

Enough babel, eh? :)

[integral]

HP Vectras are about as proprietary as they come. I doubt you can do any thing meaningful, the case is not standard, the mobo is not standard, even if these were standrad they would be AT and of little use. It is best left as is, a nice museum piece. Start from scratch and build a system, as noted above a very usable modern system can be built pretty cheap.